1xEV-DO RF Performance Engineering
Transcript of 1xEV-DO RF Performance Engineering
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1xEV-DO RF Performance Engineering
CL3724Issue 1.0
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Legal Information
This is an Alcatel-Lucent proprietary training course.
All trademarks and service marks specified herein are owned by their respective companies.
The information in this presentation is proprietary and is the sole property of Alcatel-Lucent Inc. For permission to reproduce or distribute, please contact Alcatel-Lucent at 1.720.482.6047
Copyright 2008 by Alcatel-Lucent Inc. All rights reserved.
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Course Description
CL3724 provides a basic overview of the RF engineering optimization processes unique to 1xEV-DO. Alcatel-Lucent’s suggested optimization techniques are discussed utilizing case study data gathered from in-service systems that have recently been optimized.
Case studies will be used to highlight fundamental flaws in the current RF design: such as coverage holes, dropped call regions, multiple pilot areas, and outages due to RF propagation problems. Students will be given the opportunity to resolve these problems by suggesting parameter changes. Various RF optimization techniques will be utilized by the students to improve the performance of the system under study.
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Intended Audience
This course is intended for the following audience:
1xEV-DO Radio Frequency (RF) performance engineers,
RF design engineers,
Optimization engineers,
Technicians with limited 1xEV-DO optimization experience or personnel who will be implementing additional EV-DO RF carriers.
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CDMA/1xEV-DO RF Engineering Curriculum
CL8304
3G-1X
Experienced
RF Engineers
CL3723
CL3716 (basic)
CL8300C (Experienced
engineers)
CL83022G/3G-1X
CL83032G/3G-1X
CL1522/
CL1523
CL8306
1xEV-DO
CL3724
CL8307S
EV-DO,
Rev A
CDMA
Fundamentals
RF Design
Engineering
Base Station
Call Processing
RF Performance
Engineering
Topic
System Performance
Monitoring and
Analysis Tools
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Contents
CL3724 consists of the following lessons:
EV-DO RF Performance Basics
EV-DO Handoff Matrix
EV-DO Revisions Summary
EV-DO RF Troubleshooting
EV-DO Multi-Carrier Optimization
EV-DO Quality of Service (QoS)
Alcatel-Lucent EV-DO Optimization Tools
Case Studies and Solutions
EV-DO Hardware and Other Impacts
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Course Objectives
At the end of this course, you should be able to do the following:
Describe 1xEV-DO network from an RF perspective
Identify the major factors in EV-DO RF performance and troubleshooting
Describe multi-carrier optimization
Describe QoS
Identify the features and functions of EV-DO optimization tools
Analyze EV-DO optimization case studies and outline their solutions
Describe EV-DO hardware and other Impacts
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End of CL3724 Course Introduction
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EV-DORF Performance BasicsFactors influencing performance1
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Lesson Objectives
Describe EV-DO RF optimization, its parameters and tests
Describe service measurements
Identify the key performance indicators for EV-DO RF network
Describe key factors in handoff and data throughput
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1xEV-DO Performance and Optimization
Uplink
Input
Router
Downlink Input
Router
Downlink
Input
RouterUplink
Input
Router Flexent Mobility
Server (FMS5)
Flexent Mobility
Server (FMS0)
OMP FX
(Element Management
System)
1x EV-DO BTS 1
1x EV-DO BTS 64
1x EV-DO BTS 384
1x EV-DO BTS 320
PacketData
ServiceNode
(PDSN)
AAA
Ethernet
Ethernet
IP Network
Critical Elements
Router
Internet
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RF Optimization
Several RF attributes influence performance:
RF conditions
Adequate Signal strength
Dominant Pilot coverage
Channel conditions (fading type, amount of shadowing)
Loading on the links
Proper RF parameter settings
Important part of RF optimization
Some key RF parameters on the next slide
Overlay on an existing 3G1x offers a good starting set
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RF Optimization Parameters
Neighbor Lists
CBR/UCR adjustments (cell attenuation)
Antenna adjustments (downtilt, azimuth, beamwidth)
Neighbor Search window size
Handoff parameters (Detection, Drop and Comparison thresholds; Drop Timer; Max Legs)
Access parameters
Active /Reverse Traffic Search window size
Reverse overload/power control parameters
Reverse rate transition probabilities
Tx/Rx delays
Paging and Inter-RNC handoff related
Dormancy timer
Most
Moderate
Rarely
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RF Optimization Tests
Test Set-Up
Cabled Pre-Test
Sector Testing
Cluster Drive Testing
Session Transfers: EV-DO to 3G-1X and 3G1X to EV-DO
Protocol Stack Parameter Optimization
Drive Test RF Optimization Examples
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1xEV-DO Drive Test Set-up
Test terminal
Performance/Optimization/Analysis software in laptop
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Verify the Test Set-up – Make a Test Call w/o 1xEV-DO Air Interface
Verify the drive test equipment and backhaul network w/o an RF link
BTS
RF Couplers/Attenuators to
allow direct-connect
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Sector Testing
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Cluster Drive Test Example
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Service Measurements and Key Performance Indicators
Often SM based KPIs provide initial pointer for problems affecting performance
Further investigation/detection of root cause may require drive/stationary tests
Most of such issues should have been detected prior to commercial launch
Networks are “dynamic”; so can’t identify/resolve all problems upfront
Cell adds, traffic pattern changes, subscriber growth, new AT adds
Many problems affecting performance leave similar signatures
One or more KPIs / associated metrics are impacted
Troubleshooting requires elimination of potential sources to get to the root cause
Broader effect of any performance fine-tuning on end-user performance can only be characterized via SM
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Key Performance Indicators
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Key Performance Indicators
Evaluating RF Performance in a wireless Data network centers around a few key questions:
How successfully can the calls be setup in the network?
How reliably can the calls be sustained in the network?
How’s the throughput performance (per user and sector level)?
Certain primary metrics that help address above questions are termed KPIs
Reduce a host of SM counts to a manageable starting point for analysis
Role of KPIs in
Performance evaluation
Benchmarking
Performance troubleshooting
Planning (capacity and growth)
System engineering studies
Performance feature validation
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KPIs for 1xEV-DO
KPIs are indicators of:
Coverage
Capacity
Network optimization
System provisioning
Service quality experienced at the end user
Similar to 3G1x Data network, three KPIs can be defined for 1xEV-DO Network
Established Connection (Call) Rate
Dropped Connection (Call) Rate
Data Throughput
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Analysis using KPIs
Each KPI can be computed on a per sector basis Actual analysis may be performed on a per sector basis
Several counts available with sector granularity
A particular problem may exclusively impact one or more isolated sectors
However, often a cluster of contiguous cells may be required
Impact often widespread
E.g, due to external interference, excessive loading
Skewed metrics due to mobility
E.g., call attempts may be pegged on cell, but AT has moved into neighboring cell before problem
occurs
Active set on a different cell
E.g., Failure to perform handoff with the impacted cell pegs drop call on the surrounding cell
Certain critical mass required for meaningful analysis Call attempts / data usage
Sufficient historical benchmark
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KPI: Established Connection Rate
Measure of the success with which calls can be set up
Mathematically, expressed as:
Term Definitions
Connection Requests (CR)
Similar to Origination or Termination Seizures in 2G/3G1x
Simply means an access or a call attempt to establish a connection received at
the AN from the AT (after UATI assignment)
Connection Failures (CF)
Several failures associated with call setup after traffic channel assignment
Failure to acquire mobile, other reasons
RequestsConnection
FailuresConnectionRequestsConnectionRateConnectiondEstablishe
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KPI: Established Connection Rate (cont.)
Established Connection Rate can be expressed separately for AT Initiated calls - first attempt following session establishment or
after dormancy AN Initiated calls (similar to terminations) - reactivation from
dormancy only Some important symmetrical peg counts for each call type are
listed below:
AT (AN) - Initiated Connection Request
AT (AN) - Initiated Connection Attempt Failures - Reverse Link Not Acquired
AT (AN) - Initiated Connection Attempts Failures – No Traffic Channel Complete Received
AT (AN) – Initiated Connection Attempt Failures – No Resources Available
AT (AN) - Initiated Connection Attempt Failures – Other Reasons pre-TCA
AT (AN) - Initiated Connection Attempt Failures – Other Reasons post-TCA
CR
CF
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Call Setup Flow
ControllerAT BTS
Route Update & Connection Request Msg
Allocate Traffic Channel Request
Allocate Traffic Channel ResponseAcAck
DRC Cover Indication
Send Traffic Chn AssignmentTraffic Channel Assignment
Send DRC + Pilot and ramp up
Reverse Traffic ChannelMobile Acquired Indication
Send RTC AckRTC Ack
Traffic Channel Complete Traffic Channel Complete
Ack
Configuration Negotiation Procedures
Connection Request
Traffic Channel Assigned
No TCC Received
Rev Link Not
Acquired
Negotiation Failure
Other Reasons
AT receives a command (from client or network
page) to initiate a call. AT updates overhead
messages and waits for the next Access Slot to
transmit. Assumes AT was already assigned UATI
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RF Access Failure/ Block Calls - Call Setup Flow
ControllerAT BTS
Route Update & Connection Request Msg
Allocate Traffic Channel Request
Allocate Traffic Channel ResponseAcAck
DRC Cover Indication
Send Traffic Chn AssignmentTraffic Channel Assignment
Send DRC + Pilot and ramp up
Reverse Traffic ChannelMobile Acquired Indication
Send RTC AckRTC Ack
Traffic Channel Complete Traffic Channel Complete
Ack
Configuration Negotiation Procedures
•Blocked Call
RF Access Failure
AT receives a command (from client or
network page) to initiate a call. AT updates
overhead messages and waits for the next
Access Slot to transmit. Assumes AT was
already assigned UATI
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Paging Effectiveness
AT Cell HDR
C
RouteUpdate & ConnectionRequest(AN-Initiated)
AcACK
TrafficChannelAssignment
Send DRC + Pilot and ramp up RTC
RTCAck
TrafficChannelComplete
Allocate Traffic Channel Req
DRCCoverInd
Allocate Traffic Channel Resp
SendTCA
MobileAcquiredInd
SendRTCAck
TCC
ACK
Send PagePage
TPA10 Buffer recv’d
data from the PDSN.
AT is dormant, suspend
Timer is not active
Data packets
CRinit AT Attempts PageAttemptsPaging
Failures Paging1Rate Succ Paging
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Paging Effectiveness (cont.)
Page transmission Failures Page Attempt “not responded to”
Page Attempts Page Attempts AT initiate Connection Requests
PF
PA
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Enhanced Idle State (EIS) Protocol
Permits shorter slot cycles for reducing paging delay
Permits longer slot cycles for improving battery life
Permits dynamic slot cycles defined for different ATs
Permits “not-monitored time” defined for improving paging delivery
•Connection is
•dropped and
•AT switches to
•the idle state•Period 1 duration •Period 2 duration
•Period 3 duration
•Interval 1 •Interval 2 •Interval 3
•continues for idle
•state duration
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EIS Performance Expectations
Slot Cycle 6 (SC6)= 426.67 msecSlot Cycle 7 (SC7)= 1.28 secSlot Cycle 9 (SC9)= 5.12 sec
Slot cycle i Period i
0x00 to 0x06
0x07 to 0x1c
slots 4x slotcyclei 2
slots 768 x 7 0
2
xslotcyclei
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EIS Performance Expectations – PING RTT
Slot Cycle 6
Slot Cycle 9
Slot Cycle 7
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EIS - Page Mask
The RNC will not send the AT unicast message during the Mask period.
To prevent the AT from missing a unicast message, a Page mask is
used. This allows the AT to specify periods during its idle state when the
AT will tune away to monitor different technologies (e.g., 3G1x paging,
IEEE 802.11).
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Block Call Rate
Defined as Traffic channel Assignment denied
Maximum users reached on all sectors reported in the Route Update Message for a given Connection Request
ASIC or MAC indexes limitations.
Maximum number of users reached, HROC not able to release connections.
CPFAIL# 15007=CPFAIL_CARRIER_SELECTION_FOR_TRAFFIC_CHANNEL_FAILED
Some components of Other Reasons
E.g., calls blocked due to total dormant sessions on a TP exceeding limit. There is a finite number of session the RNC can support
“TP Utilization Threshold”, currently set to 85%.
No specific blocking due to power overload
Different than 3G-1X where IAOC can block calls.
Forward link when transmitting always uses fixed full power
Reverse link power is managed by controlling transmission rates via Reverse Activity Bit (RAB) or Rate Limit mechanisms
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Fast Connect Call Flow
ControllerPrior connection ended normally.
AN received Conn Close with
Suspend flag enabled. AN receives
data from the network while AT is
in suspend mode (<5sec from the
prior Conn Close). AN decides to
invoke Fast Connect
BTS
Allocate Traffic Channel Request
Allocate Traffic Channel Response
DRC Cover Indication
Send Traffic Chn AssignmentTraffic Channel Assignment
Send DRC + Pilot and ramp up
Reverse Traffic Channel Mobile Acquired Indication
Send RTC AckRTC Ack
Traffic Channel Complete Traffic Channel Complete
Ack
Fast Connect (request)
FC TCA Sent
FC Fail - No
TCC Rcvd
FC Fail - Rev
Link Not
Acquired
FC Fail No Resources
FC - Established
Conn
Blocks
RF Failures
RequestsConnectFast
TCAtoespRNoFailuresConnectFastConnectsFastforRateCalldEstablishe
_1
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Drop Call Rate
Measure of unintended interruptions / call releases due to RF or network impairments
• Mathematically, expressed as:
• Unintended Connection Releases
• Similar to Lost call or CPFAIL call shutdown for 2G/3G1x
• CPFAIL# 44000=CPFAIL_REVERSE_LINK_LOST_IN_CONNECTED
• CPFAIL# 420XX= Several Causes
• Two main peg counts
• Connection Released - RF Link Lost
• Connection Released - Other Reasons
• Established Connections
• Connection Requests minus Connection Failures
• Derived from numerator for Established Connection Rate metric
sConnectiondEstablishe
ReleasesConnectionUnintendedRateCallDrop
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How is a Call Dropped ?
• Connection Released - RF Link Lost –
Two ways this can happen:
• Cell can no longer decode DRCs at all handoff legs, possibly because:• Of bad Reverse Link: excessive path loss, external interference, mobile has tuned away to
receive a voice call on 3G1x or has spent too much time on a particular 3G1x search in hybrid mode
• AT loses forward link (erased frames), can’t recover within DRC Supervision Timer (240 ms), stops transmission of the Reverse Link
• Handoff failures • Cell sends Traffic Channel Assignment but times out waiting for Traffic Channel Complete
message after 3 attempts
• Handoff flow illustrated on the following slide
• Cell times out waiting for any “Ack” required message (such as, Neighbor List message) after 3 tries on the Forward Traffic channel
• Connection Released - Other Reasons• Internal software errors
• Timeouts
• Failure building/sending messages
• Call states not in sync between TP and AP
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Handoff Example
Pilot
Strength
T_ADD
T_DROP
Send Route Update
Above T_ADDRecv’ TCA
Move Pilot to
Active Set
Sends TCC
BS sends
TCA
Below T_DROP
Starts T_TDROP
timer
Timer expires
Sends RU msg
BS sends TCA
Moves Pilot
To the Neig. Set
Send TCC
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Handoff Call Flow (Soft Add or Drop)
Connection Released -
RF Link Lost
Soft/er HO failures
due to no AT Response
Controlle
r
AT Existing
BTS
Route Update Message
Allocate Traffic Channel Req.
Allocate Traffic Channel Response
ACK
Send Traffic Channel AssignmentTraffic Channel
Assignment
Traffic Channel
Complete Traffic Channel Complete
ACK
New
BTS
Soft/er HO failures -
no resources
Soft/er HO Other
failures - post TCA
Soft/er HO Other
failures - pre TCA
Soft/er HO attempts
Soft/er HO TCA Sent
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Inter-RNC Idle Handoff - Call Flow
UATI Request
A11 Reg Request
A11 Reg Resp
UATI Assignment
UATI Complete
(request Upper Old UATI)
(Upper Old UATI)
Assign First(CC+UATI 024)IS Xfer Attmpt
Fail Other Reason
Fail No Resp Prev Subnet
A13 Conf
A13 SI Req.
A13 SI Resp.
Release Session
PDSN Can’t Connect
Source IP Addr Not FoundReject
LEGENDAT Target RNC Source RNC PDSN
Common
A11 Reg Udpate
A11 Reg Ack
Attempts
Failures
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Inter-RNC Idle handoff success:
A comprehensive characterization of inter-RNC idle handoff session setup success rate
Includes failures encountered during A13 session transfer
Includes Prior Session / Color Code / Assign First
•Same metric regardless of the method chosen (Color Code or Assign First)
Failures
INT_SUBNET_IDL_TRFR_FAIL_OTHER_REASON(main reason is target RNC did not receive UATI complete from the AT)
ISBNT_IDL_TRFR_FAIL_RJCT_MSG_RCVD(A13 Reject msg sent by source RNC as it could not locate the UATI since its session was already closed)
ISBNT_IDL_TRFR_FAIL_SRC_IP_ADR_NT_FOUND
ISBNT_IDL_TRFR_FAIL_NO_RSP_ PRV_SBNET
ISBNT_IDL_TRFR_FAIL_ORG_PDSN_CANT_CONN
ISBNT_IDL_TRFR_FAIL_PRIOR_SES_NO_RSP
INT_SUBNET_IDL_TRFR_PRIOR_SES_BAD_REQ
Requests SetupSession subnet -Inter
Failures SetupSession subnet -Inter 1Rate Success HO ISub
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Data Throughput
Defined as amount of data transferred per unit time
Two different measurement points
End user experience
Sector level capacity
Throughput can be characterized at various protocol layers
RLP layer offers a suitable measurement point Can be computed readily from existing SM counts
Rev. A introduced different QoS flows: Best Effort, Convers. Speech, Convesr. Video, etc
Higher layers (PPP/IP/TCP/Application) outside our infrastructure
Lower layer (Physical) too far away to reflect proper end user experience
Mathematically, can be expressed as (in kilobits per sec or kbps)
SubpacketsFramesTimeSlots
hourinreceivedd or transmitteoctetsRLPOriginalThroughputSectorreverseForward
81
100010
81
SectorPersConnectionActiveAverage
hourinreceivedd or transmitteoctetsRLPOriginalThroughputUserPerreverseForward
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Data Throughput (Cont.)
Each throughput metric can be computed separately for forward and reverse links
Term Definitions
Number of Original RLP Octets Transmitted in 1 hour Includes original data only (that is, no RLP layer retransmissions)
Bytes sent to the AT on the downlink
Note some RLP data may never reach the AT either because RLP NAK or RLP re-transmission is lost over the air
No way to account for it (usually very small - of the order of 0.02%)
Number of Original RLP Octets Received in 1 hour Includes original data only (that is, no RLP layer retransmissions)
Bytes sent by the AT on the uplink
Average Active Connections per Sector Computed similarly as the Erlangs counts in 2G/3G1x
Every 10 seconds, AP increments a counter with the # of active users on the sector
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Data Throughput dependencies
Achieved throughputs are a function of transmitted packet rates
Transmission rates in turn depends on several factors
Amount of data to be sent (backlog) Application dependent
Internet delays
Transport protocol (TCP/UDP)
Backbone network issues (packet drops, routing configuration)
Client and server configuration issues
RF conditions (coverage, mobility, dominant pilot, etc.) For forward link, AT itself requests rate to be able to achieve 1% packet error
On the reverse link, AT may lower rates if it estimates insufficient transmit power headroom
Loading conditions Fwd link - the more the # of active users, the fewer the slots per user
Rev link - overload control to manage AT transmitted rates
All backbone network integrity related issues need to be resolved prior to/ in the
initial stages of commercial use
Using controlled stationary and drive tests
Difficult to pinpoint with SM
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Forward Link Scheduler Rel. 0
Alcatel-Lucent supports Proportional Fair Scheduler on the forward link
Proportional -At a given instant, AT experiencing strongest SNR (and hence requesting highest DRC rates) has a higher probability of getting serviced in a given sector
Fair - In a typical field environment, short term RF variations cause SNR at individual users within a sector to peak at different times, so high likelihood of giving everybody a chance
Goal is to maximize sector throughputs while minimizing data starvation for the disadvantaged users
Serve the AT with the highest ratio of [ current_DRC / short_term_filtered_average_of_transmitted_rate ]
Hold back data for other users until the ratio improves
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Forward Link Scheduler Rev. A
RTx Queue
FTx Queue
DARQ Queue
Flow a
Flow b
Flow x
User 1
User 2
User n
Calculate bit stuffing metrics for each flow
Generate a list of candidate Instances
Select one (or several) best candidate Instance(s)
Maximize the packing efficiency
Calculate a priori probability (Optional)
Make scheduling decision
FL Scheduler
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Forward Link Scheduler Rev. A
Mac Flow Layers Example Bound Priority
Signaling SLP and etc… Naks, auth, etc… AN 1
Speech Application VoIP or VT SN 2
Video-48K Application VT SN 3
CMCS Application SIP SN 4
BE Application FTP SN 5
Video 48
Speech
CMS
BE
Scheduler
EV-DO Modem (EVM) Card
Δ Time = Queue time
MAC L
ayer P
acket A
rrival
PH
Y L
ayer P
acket O
TA Tra
nsm
ission
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Reverse Link Rate Control Rel. 0
No specific scheduling algorithm on the reverse link
Each user can transmit at max allowed rate subject to AT’s view of available tx headroom and backlog
Cell manages maximum allowed rates in overload conditions
Preserve coverage
Avoid instability due to overload
Maintain DRC and ACK channel performance - important for fwd link throughputs
Two methods
Reverse overload control using Reverse Activity Bit (RAB)
If the bit is set, AT will probabilistically halve its transmission rates
Coupled with rate transition probabilities
Cell will set the bit when overload conditions based on estimated loading (depends on number of users and received energy levels) and RSSI are met
Rate Limit
Active only when RAB based control is disabled
Cell will lower the maximum rate broadcast on the Control channel
Translations settings for max allowed users for each rate
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Reverse Link Rate Control Rev. A
Token Bucket Single Flow
T2Pinflow
(new resource based on RNC assigned priority to flow)
BucketLevelSat(maximum allowed bucket size)
BucketLevel(unused accumulated resource)
PotentialT2POutput(maximum allowable withdrawal)
DataT2POutflow
(actual T2P withdrawal)
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Reverse Link Rate Control Rev. A
High T2PInflow Zero Inflow
RAB from
BTS
T2PInflow
Multiplexe
r(flow
properties,
QoS)
Select PS;
Subject to
several
constraints
PHY. TM
T2
PO
utflo
w
T2
PO
utflo
w
TxT2P
PotentialT2POutflow
PotentialT2POutflow
T2
P_
to_
Q
QRAB
Token Bucket Multiple Flow
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Short and Long Term RAB Filtering
All of the RAB bits received from all the sectors in its active set are
logically ORed and are filtered.
•RAB bits•from all•sector in•active Set
RABDetector
Short termIIR Filter
Samplingat 6.67-ms
rate
Samplingat 6.67-ms
rate
Long termIIR Filter
(4 slotsdefault TC)
(384 slotsdefault TC)
•FRAB
•QRAB
-1,1
-1,1
-1,10, 1
AT
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T2PInflow Equation
T2PInflow
ni,ΔT2PInflow
ni,T2POutflow1/τ
1-ni,T2PInflowτ11
ni,T2PInflow
T2POuflow
1QRAB
1QRAB
,T2P,FRABT2PUp
,T2P,FRABT2PDn
ni,ΔT2PInflow
1QRABPb
b1-
bPriority
T2PDn
T2PUp
01QRABPT2PUp1QRABPT2PDn-
0ΔT2PInflowET2POutflowET2PInflowE
T2PInflow is updated according,
where,
At steady state,
Steady state T2PInflow
(determines resource
allocation, QoS) is obtained by
solving this equation
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Priority function Example
The long term T2PInflow is one the factors that determines QoS of the flow
Long term T2PInflow is determined by the intersection of “priority function” and loading “b/(1-b)”
Three flows, red has fixed allocation (delay sensitive), blue has a fixed allocation but can benefit from higher rate (delay sensitive) and green elastic allocation (delay tolerant) and uses available resource to achieve high rates
Priority Functions
-25
-20
-15
-10
-5
0
5
10
15
20
25
0 5 10 15 20 25
T2PInflow
T2P
Up
/T2P
Dn
Flow 1 Flow 2 Flow 3 b/(1-b)=-10 b/(1-b)=0 b/(1-b)=1 b/(1-b)=17
High RoT
Low RoT
b/(1-b)
T2PInflow vs. loading
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
17
16
15
14
13
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
20
19
18
17
16
15
14
13
12
11
10 9 8 7 6 5 4 3 2 1
0
5
10
15
20
25
30
35
40
45
50
-10 -8 -6 -4 -2 0 2 4 6 8
10
12
14
16
18
20
b/(1-b) dB
T2P
Infl
ow
Flow 3
Flow 2
Flow 1
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3G1X HSPD vs EV-DO Rev.0 HDR vs EV-DO Rev.A HDR
RX Power
dB
Ec/Io
dB
SINR
dB
DRC
kbps
Download
FTP
kbps
Upload
FTP
kbps
Download
HTTP
kbps
Upload
HTTP
kbps
Latency
ms
-70.79 -3.27 na na 125 138 146 140 332
-64.48 -1.45 9.96 2,184 1,189 150 1,313 150 149
-68.60 -1.47 9.81 2,130 923 150 1,246 151 206.07
-63.08 -0.97 11.66 2,873 1,261 818 1,352 944 84.51
-63.61 -1.49 9.89 2,638 685 766 848 881 149
•3G1X HSPD
•EVDO R.0
•EVDO R.A
•Average of numerous drives in 2 small cities – different sites each drive
Expectations –Examples
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Lesson Summary
At the conclusion of this lesson, you should be able to
Describe EV-DO RF optimization, its parameters and tests
Describe service measurements
Identify the key performance indicators for EV-DO RF network
Describe key factors in handoff and data throughput
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CL3724: End of Lesson
Do not delete this graphic elements in here:
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EV-DO Handoff Matrix (HOM)2
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Why HOM?
Handoff matrix data is used to adjust neighbor lists and improve handoff performance.
HOM is an on-demand tool which users run on the OMP when HOM data is needed. Unlike service measurements data, the HOM tools are NOT running all the time.
The EV-DO HOM tools are similar to the CDMA HOM (handoff matrix) tools with several significant differences.
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What Does EV-DO HOM Do?
The EV-DO HOM tool is explained in this module.
For a single service node (SN) and for a specified period of time,
EV-DO HOM counts the undeclared neighbors and the successful and
attempted handoffs from each sector in the SN to every other
sector in the system.
It reports the following:
Added and dropped legs – both completed and attempted for:
Soft and softer handoffs
Soft, softer, and hard handoffs
Undeclared neighbors* (using PN offset) for each sector
The start and end times of the handoff data collection
*An undeclared neighbor is a PN offset that is not in the current set of strongest pilots for the AT
but is strong enough for the AT to propose as a handoff candidate. Undeclared neighbors that
occur frequently in HOM data may need to be added to neighbor lists.
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How Does EV-DO HOM Work?
During an EV-DO HOM Study, each successful add or drop of a call leg
from active sessions is recorded as a handoff. Attempts are counted
also.
Each AP maintains a matrix where it counts the number of handoffs
and the undeclared neighbors for each source and target pair of
sectors (the “From” sectors and the “To” sectors).
At the end of the study, the counting stops automatically and is stored
on the APs until the user requests a report of the accumulated data.
The OMP pulls all the HOM data from all the APs that collected it and
merges it into one ascii file on the OMP.
The data is written on the OMP in a default directory on the OMP in
the format specified by the user.
Idle transfers and handoffs from idle sessions are not reported.
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How Do I Use EV-DO HOM?
To start an EV-DO HOM study:
/omp/bin/evstarthom [-h][-t DURATION]
-h Display the help information
-t Duration of the study (10-1440 minutes, default is 10 minutes)
To collect EV-DO HOM data or to stop a running study early:
/omp/bin/evdisphom [-o file_name] [-fshw]
-o Output file name for HOM data
-f Output the data in colon-delimited format. With no –f option, data is output in table format.
-s Stop a study early, before its duration has elapsed. No data is collected.
-h Display the help information
-w Wait for no longer than 15 minutes to collect data. When used with –s, study is stopped and data is written to a file on the OMP shortly after the data is available from the APs.
Users who want to run these commands must use logins that are in the ECP group on the OMP.
The new FAF for EV-DO HOM must also be active.
HOM data file is written in /omp-data/logs/hom/evdo_summary_files.
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What Data Does EV-DO HOM Collect?
EVDO HANDOFF MATRIX RELEASE 25.0Start Date: 08/29/2005 Start Time: 08:00:26Stop Date: 08/29/2005 Stop Time: 23:00:02Service Node ID: 33 Reporting RNC(s): 20, 21, 22
DECL: DECL: TO CELL TO
TO UNDEC: SECT TO FROM FROM SECT PN UNDEC: ACTIVE ADD ADD DROP DROP CELL SECT DECL OFFSET CHAN# AP IP COMPL ATTEMP COMPL ATTEMP83 2 N 108 875 N/A N/A 1 N/A N/A83 2 Y 113 2 10.204.232.15 1 1 1 183 2 Y 113 3 10.204.232.15 5 6 5 583 2 N 128 875 N/A N/A 2 N/A N/A83 2 Y 133 1 10.204.232.8 8 9 9 983 2 Y 133 3 10.204.232.8 3 3 5 583 2 Y 138 1 10.204.232.10 0 6 0 083 2 N 140 875 N/A N/A 1250 N/A N/A83 2 N 156 875 N/A N/A 2 N/A N/A
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Lesson Summary
At the conclusion of this lesson, you should be able to
Identify the main RF optimization tools for EV-DO
Describe the features and functions of HOM
Analyze sample reports from various RF optimization tools
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CL3724: End of Lesson
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65
EV-DO Revisions Summary3
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Lesson Objectives
Give a brief summary on EV-DO revisions
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EV-DO Evolution and Differentiators
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Enhanced DO and DO Rev A Evolution
Other
MSM5500 MSM6500 MSM6550 MSM6800
CSM5500
CSM6800
EV-DO Rev 0
Device HW BTS HW EV-DO Capability
PDSN and AAA Enhancements MSM5500 MSM6500 MSM6550 MSM6800
CSM5500
CSM6800
EV-DO Inter-User QoS
Content Server, Controller, Sub Database/ Manager
MSM6500 MSM6550 MSM6800
CSM5500
CSM6800
EV-DO BCMCS w/o Enhanced Physical Layer
PDSN and AAA Enhancements MSM6500 MSM6550 MSM6800
CSM5500
CSM6800
EV-DO Intra-user QoS
PDSN and AAA Enhancements MSM6800 CSM6800 EV-DO Rev A Enhanced Physical Layer
PDSN and AAA Enhancements MSM6800 CSM6800 EV-DO Rev A QoS
Content Server, Controller, Sub Database/ Manager
MSM6800 CSM6800 EV-DO Rev A BCMCS (Gold/ Platinum)
Enhanced PDSN and AAA IMS Core
MSM6800 CSM6800 EV-DO Rev A w/ VoIP
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Rev A Benefits
Improved Forward Link Larger payloads drive data rates to
3.1Mbps
Improved MAC supports over 100 users per sector
Packet Division Multiplexing improves performance in good channel conditions
New Channel enabling Increased Forward Throughput
Improved Reverse Link Up to 1.8 Mbps data rate
Throughput and latency gains with hybrid ARQ
Improved MAC Layers on reverse link
Quality of Service (QoS) Inter-User – Priority by User
Intra-User – Priority by Application
Requirements for VoIP/PTT applications
Broadcast/ Multicast Service (BCMCS)*
Multimedia content to multiple users
Improved support for real-
time packet applications,
including VoIP, Gaming, Push-
to-Talk (PTT)
Can leverage advanced all-IP
architectures to further
improve performance and
deployment flexibility
Enhanced capabilities to
enable service flexibility and
new revenue generating
features
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Rev 0 vs. Rev A Data Rates
38.4 kbps
76.8 kbps
153.6 kbps
307.2 kbps
614.4 kbps
921.6 kbps
1,228.6 kbps
1,843.2 kbps
2,457.6 kbps
9.6 kbps
19.2 kbps
38.4 kbps
76.8 kbps
153.6 kbps
Forward Link Reverse Link
Rev 0 Data RateRev 0 Data Rate
Rev A Data RateRev A Data Rate
4.8 kbps
9.6 kbps
19.2 kbps
38.4 kbps
76.8 kbps
153.6 kbps
307.2 kbps
614.4 kbps
921.6 kbps
1,228.6 kbps
1,536.0 kbps
1,843.2 kbps
2,457.6 kbps
3,072.0 kbps
4.8 kbps
9.6 kbps
19.2 kbps
38.4 kbps
76.8 kbps
115.2 kbps
153.6 kbps
230.4 kbps
307.2 kbps
460.8 kbps
614.4 kbps
921.6 kbps
1,228.6 kbps
1,843.2 kbps
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Rev A Performance
Reverse linkRLP throughput
Number of activepacket data usersper sector-carrier
Number of VoIPcalls per sector-carrierwith 2% blocking
-Four way receive diversity
-Two way receive diversity
AT with single antenna
AT with dual antenna
Dual antenna receiveforward and reverse links
Dual antenna receiveforward and reverse links
200 kbps
1000 kbps 1100 kbps
800 kbps
680 kbps
400 kbps
700 kbps
340 kbps
Rev 0 Rev A
20
N/A
30
45 (35 Erlang)
Forward linkRLP throughput
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New Rev A Protocols
New Protocols
added in Rev A
Adapts data
reliability, latency,
and data rate for
each session as a
function of its QoS
requirement
Comparable Rev 0
protocols are the
default protocol
Although major
changes in Rev A are
at the MAC and
Physical layers,
protocol changes
occur on every
layer except Session
and Security layers
Multi-flow Packet Application
Flow ControlProtocol
Radio Link
Protocol
Location Update Protocol
Data Over Signaling Protocol CDMA2000
Circuit Services
Notification Protocol
CDMA2000 Circuit Services Notification
Application
Multimode Capability Discovery Protocol
Multimode Capability Discovery
ApplicationApplication
Layer
Enhanced Forward Traffic Channel MAC
Protocol
Enhances Control Channel MAC
Protocol
Subtype 2 Reverse Traffic Channel MAC
Protocol
Enhanced Access Channel MAC Protocol
Subtype 3 Reverse Traffic Channel MAC
Protocol
Subtype1 Reverse Traffic Channel MAC
Protocol
Stream Layer
Session Layer
Mac Layer
Security Layer
Connection Layer
Physical Layer
Virtual Stream Protocol
Session ManagementProtocol
Address ManagementProtocol
Session ConfigurationProtocol
Enhanced Idle State Protocol
Generic SecurityProtocol
DH Key ExchangeProtocol
SHA-1 AuthenticationProtocol
Subtype 1 Physical Layer Protocol
Subtype 2 Physical Layer Protocol
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Lesson Summary
At the conclusion of this lesson,
you should be able to
Know about EV-DO revisions
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CL3724: End of Lesson
Do not delete this graphic elements in here:
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EV-DO RF TroubleshootingTroubleshooting Techniques
Resolution4
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Lesson Objectives
Perform basic troubleshooting of RF problems (such as lack of coverage, excessive pilots, interference, and non-optimized neighbor lists)
Examine inter-RNC border issues and RNC grouping
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Lack of RF Coverage
Description
Inability to close either link
Reverse link more susceptible compared to fwd link esp. at higher RF loading
Areas suffering from heavy shadowing (in-building, route blocked by buildings, trees, etc.)
Impact on all 3 KPIs
Symptoms / Identification Techniques
First identify the affected area by focusing on cells with simultaneous impact on several SM metrics
Low Established Call rate
High Dropped call rate
Low Data Throughput
High RLP re-transmission rate ratio of RLP Octets Re-transmitted to RLP Octets Transmitted on the fwd link
ratio of Missing RLP Octets Requested to RLP Octets Received on the rev link
Best detected via drive tests / stationary sampling AT rx power < -105 dBm, AT rx SNR < -10dB, AT transmit power > 20 dBm
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Lack of Coverage – Link Supervision
AT supervises the forward link by monitoring its own DRC Channel
See flowchart
RAN supervises the reverse link by monitoring the AT’s DRC Channel
If only a small number of good DRCs are received during a certain time period, then the connection is released.
Transmit DRC
Consecutive
null-rate DRC for
TFTCMDRCSup
?
No
Yes
No
Yes
Stop RTC
Less than
NFTCMPRestartTx consec.
non-null-rate DRC for
TFTCMPRestart
?
Abandon connection
Start RTC
TFTCMDRSupervision = 240 ms
TFTCMPRestart = 5.12 s
NFTCMPRestartTx = 16 slots
TFTCMDRSupervision = 240 ms
TFTCMPRestart = 5.12 s
NFTCMPRestartTx = 16 slots
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RF Access Failures – Established Connection Rate
•AT didn't receive AcAck message
•Max. Number of Probes reached.
•Weak RF Conditions. Ec/Io of Ref PN -10 dB.
• AT didn't receive TCA/RTCAck or the AT shut off reverse link transmitter due to DRC supervision failure and because of this AN couldn't acquire AT on the reverse link
Access Failure
Access Failure
Access Failure
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Access Procedure
x = - Mean Rx Power (dBm) + x0 = - Mean Rx Power (dBm) +
OpenLoopAjust + ProbeInitialAdjust
PersistenceTest
1 2 3 N1
1
PersistenceTest
1 2 3 N2
2
PersistenceTest
1 2 3 Np
NsProbe Sequence No.
PowerIncrements
Step
~ ~
Ts
x0
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Enhanced Access Channel (EAC) MAC
Transmit Power
Preamble9.6 kbps Data Channel
Pilot Channel
1 Frame 4 Frames
Transmit Power
Preamble
19.2 kbps Data Channel
Pilot Channel
4 slots2 Frames
REV 0 Access Channel
Transmit Power
Preamble 9.6 kbps Data Channel Pilot Channel
4 slots4 Frames
Transmit Power
Preamble
38.4 kbps Data
Channel
Pilot Channel
4 slots1 Frame
Access Channel Capsule
Access Channel Capsule
Access Channel Capsule Access Channel
Capsule
REV A Access Channel
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Pilot Strength Correction Factor (PSC)
Open Loop Power Control for AT’s transmit Power:
Ec/Io of the desired sector to which access probes are directed:
Rev. A modifies the ProbeInitialAdjust and makes it dynamic:
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EAC and PSC Expectations
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Access Channel Translations
SN General – General 2
SN Pilot
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Access Channel Translations
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Translation Parameters: Recommended Values
Preamble Length Slots: 4, (Service Node – Enhanced Access Channel, Sector Carrier – Enhanced Access Channel)
Probe Time Out Adjust (in units of 16 slots): 0, (Service Node –Enhanced Access Channel, Sector Carrier – Enhanced Access Channel)
Sector Access Max Rate (kbps): 38.4, (Service Node – Enhanced Access Channel, Sector Carrier – Enhanced Access Channel)
Pilot Strength Correction Min (dB): 0, (Service Node – Enhanced Access Channel, Sector Carrier – Enhanced Access Channel)
Pilot Strength Nominal (dB): 0, (Service Node – Enhanced Access Channel, Sector Carrier – Enhanced Access Channel)
Pilot Strength Correction Max (dB): 5, (Service Node – Enhanced Access Channel, Sector Carrier – Enhanced Access Channel)
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Translation Parameters: Recommended Values (Cont.)
Terminal Access Rate Max (kbps): 9.6, (Service Node – Enhanced Access Channel MAC)
EAC Power Offset Nominal (2’s complement in units of 0.5dB): 0, (Service Node – Enhanced Access Channel MAC)
EAC Power Offset 9k6 (2’s complement in units of 0.25dB): 0, (Service Node – Enhanced Access Channel MAC)
EAC Power Offset 19k2 (2’s complement in units of 0.25dB): 0, (Service Node – Enhanced Access Channel MAC)
EAC Power Offset 38k4 (2’s complement in units of 0.25dB): 0, (Service Node – Enhanced Access Channel MAC)
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Enhanced Control Channel
•0
•0
•1
•1
•2
•2
•3
•3
•2•5•4
•2•5•4
•2•5•5
•2•5•5
•2•5•6
•2•5•6
•2•5•8
•2•5•8
•Arrival of•page at
•Base Station
•Arrival of•page at
•Base Station
•2-slot•offset
•2-slot•offset
•page•TX Start
•page•TX Start
•page•TX end
•page•TX end
•Control Channel Cycle
•Control Channel Cycle
•256 slots (426.66 ms)
•256 slots (426.66 ms)
•Connection setup time reduction
•Sub-sync control•channel cycle
•64 slots (106.66 ms)
•6•6
•1•3•0
•1•9•4
•Rev 0 Control Channel Cycle
•Rev A Control Channel Cycle
•Synchronous•control channel
•Packet
•Asynchronous•control channel
•Packet
•Sub-synchronous•control channel
•Packet
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Lack of Coverage – Drop Call Rate
Dropped Call
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Lack of Coverage – Drop Call Rate
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Lack of Coverage – Data Throughput
Low Throughput = Low SINR
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Lack of RF Coverage (cont.)
Mitigation Strategies
Drive test based optimization to improve and verify coverage changes
Antenna adjustments (azimuth, remove excessive downtilt)
Use a higher beamwidth antenna
Add a repeater (esp. for in building locations)
Add a cell
Secondary benefits possible in terms of overall performance improvement
Improved pilot coverage on forward link can result in improved DRC rates
Except CBR option, all others improve rev link coverage, possible reduction in
interference due to AT power mitigation
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Excessive Pilots
Cell 22
Cell 91
Cell 121
Cell 201
Cell 150
Cell 72AT in 3-way Soft Handoff
PN156
PN216
PN300
PN186
PN234
PN330
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Excessive Pilots (Cont.)
Symptoms / Identification Techniques
On a relative basis (compared to other cells), look for cells with higher value of:
Ratio of “Greater than 1-way CRs” to “Total CRs”
[ Connection Requests with 3 or more Pilots + Connection Requests with 3 Pilots + Connection Requests with 2 Pilots ] / [AT + AN Initiated Connection Requests]
Soft and softer handoff attempts (excessive HO activity)
Although more indicative of mobility, combine with other metrics
In case of one-to-one overlay on an existing 2G/3G1x system, look for pilot pollution using 2G/3G1x SM on the underlying cells:
High ratio of Total Walsh Code to Primary or Secondary CE to Total CE usage
High instances of candidate Pilots seen above Tadd/Tcomp
Handoff Matrix analysis for high soft/er handoff %
Undeclared Neighbor List to locate overshooting pilot not in the neighbor list
Simultaneous impact on Est. Connection Rate and Data Throughput
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Excessive Pilots (Cont.)
Mitigation Strategies
Similar to Lack of RF coverage, drive tests more effective
Assuming wide enough impact on the routes
RF optimization efforts aimed at creating dominant Pilot
CBR (simultaneous adjustment - up on some cells/down on others)
Antenna adjustments (downtilt, azimuth)
Add a cell if all efforts to break the tie fail
usually such areas also have low or marginal coverage
Minimize impact from the distant overshooting Pilot (“kill it or use it”)
CBR increase or downtilt
Otherwise, include in the neighbor list
Active/Optimize the SoftSlope Handoff Algorithm
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Problem Areas Identified
Best ASP SINR
(dB)
20 to 100 (0)
10 to 20 (159)
5 to 10 (960)
0 to 5 (1327)
-5 to 0 (748)
-10 to -5 (73)
-30 to -10 (1)
Overlay
Origination Failure (1)
Low Throughput Areas
Low throughput and Origination
Failure
Area 1
Area 2
Area 3
Area 6
Area 3
Area 4Area 5
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Average RLP TP
0.00
0.25
0.50
0.75
1.00
RLP Throughput - ForwardMean = 644.907 Std Dev = 385.904
4054 occu
rences
kbps[0,1) [1,80) [80,270) [270,450) [450,700) [700,1000) [1000,2500)
PDF CDF
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Low SINR Area 1 - Pilot Pollution
2_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_500
2_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_132
2_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_352
29_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_504
29_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_84
29_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_392
36_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_340
36_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_324
36_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_400
75_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_12
75_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_108
75_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_56
78_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_336
78_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_428
91_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_64
91_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_116
91_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_476
100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16
180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436
182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332
182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380
182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268
121212121212121212
161616161616161616
161616161616161616
121212121212121212
121212121212121212
565656565656565656
565656565656565656
565656565656565656
565656565656565656
565656565656565656
108108108108108108108108108
108108108108108108108108108
108108108108108108108108108565656565656565656
565656565656565656
116116116116116116116116116565656565656565656
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116116116116116116116116116116108108108108108108108108108332332332332332332332332332332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
436436436436436436436436436
436436436436436436436436436969696969696969696
436436436436436436436436436
332332332332332332332332332332332332332332332332332332324324324324324324324324324
324324324324324324324324324
436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268
268268268268268268268268268
432432432432432432432432432
432432432432432432432432432
848484848484848484
268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332
340340340340340340340340340340340340340340340340340340332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332
340340340340340340340340340
340340340340340340340340340
340340340340340340340340340
332332332332332332332332332
340340340340340340340340340
340340340340340340340340340
108108108108108108108108108
108108108108108108108108108
108108108108108108108108108
116116116116116116116116116268268268268268268268268268116116116116116116116116116116116116116116116116116116268268268268268268268268268
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
268268268268268268268268268116116116116116116116116116404040404040404040404040404040404040504504504504504504504504504404040404040404040404040404040404040
504504504504504504504504504
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
104104104104104104104104104
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
99
Low SINR Area 1 - Pilot Pollution [Cont.]
BestASPPN CountOfBestASPPN AvgOfAvgOfATReceivePower AvgOfAvgOfBestASPEcIo
116 62 -71.5 -6.7
268 14 -73.5 -6.8
504 5 -74.8 -7.8
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
100
Low SINR Area 2 – Pilot Pollution
1_1_401_1_401_1_401_1_401_1_401_1_401_1_401_1_401_1_40
1_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_3_1481_3_1481_3_1481_3_1481_3_1481_3_1481_3_1481_3_1481_3_148
2_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_500
2_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_132
2_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_352
29_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_504
29_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_84
29_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_392
75_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_12
75_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_108
75_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_56
88_1_5288_1_5288_1_5288_1_5288_1_5288_1_5288_1_5288_1_5288_1_52
88_2_21288_2_21288_2_21288_2_21288_2_21288_2_21288_2_21288_2_21288_2_212
88_3_30888_3_30888_3_30888_3_30888_3_30888_3_30888_3_30888_3_30888_3_308
91_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_64
91_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_116
91_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_476
125_1_72125_1_72125_1_72125_1_72125_1_72125_1_72125_1_72125_1_72125_1_72
125_2_120125_2_120125_2_120125_2_120125_2_120125_2_120125_2_120125_2_120125_2_120
125_3_368125_3_368125_3_368125_3_368125_3_368125_3_368125_3_368125_3_368125_3_368182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332
182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380
182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268
161616161616161616
121212121212121212
121212121212121212
565656565656565656
565656565656565656
565656565656565656
565656565656565656
565656565656565656
565656565656565656
108108108108108108108108108
108108108108108108108108108
108108108108108108108108108
108108108108108108108108108565656565656565656
565656565656565656
565656565656565656
116116116116116116116116116565656565656565656
116116116116116116116116116
116116116116116116116116116
332332332332332332332332332
116116116116116116116116116
116116116116116116116116116268268268268268268268268268332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332108108108108108108108108108
268268268268268268268268268
268268268268268268268268268
116116116116116116116116116
432432432432432432432432432
268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332
268268268268268268268268268116116116116116116116116116268268268268268268268268268116116116116116116116116116116116116116116116116116116116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
268268268268268268268268268116116116116116116116116116504504504504504504504504504404040404040404040268268268268268268268268268504504504504504504504504504504504504504504504504504504404040404040404040132132132132132132132132132
504504504504504504504504504
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
101
Low SINR Area 2 – Pilot Pollution [Cont.]
BestASPPN CountOfBestASPPN AvgOfAvgOfATReceivePower AvgOfAvgOfBestASPEcIo
132 98 -70.5 -5.8
504 46 -70.4 -6.2
40 19 -72.7 -6.6
212 1 -65.2 -4.8
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
102
Low SINR Area 3 – Pilot Pollution
1_1_401_1_401_1_401_1_401_1_401_1_401_1_401_1_401_1_40
1_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_2_1721_3_1481_3_1481_3_1481_3_1481_3_1481_3_1481_3_1481_3_1481_3_148
6_1_46_1_46_1_46_1_46_1_46_1_46_1_46_1_46_1_4
29_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_504
29_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_84
29_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_392
36_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_340
36_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_324
36_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_400
63_1_43263_1_43263_1_43263_1_43263_1_43263_1_43263_1_43263_1_43263_1_432
63_2_16463_2_16463_2_16463_2_16463_2_16463_2_16463_2_16463_2_16463_2_164
63_3_14063_3_14063_3_14063_3_14063_3_14063_3_14063_3_14063_3_14063_3_140
180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436
180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316
180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328
182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332
182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380
182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268
187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296
187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376
187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
268268268268268268268268268504504504504504504504504504108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108108108108108108108108108108332332332332332332332332332332332332332332332332332332332332332332332332332332332
436436436436436436436436436324324324324324324324324324436436436436436436436436436436436436436436436436436436436436436436436436436436436380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380296296296296296296296296296380380380380380380380380380380380380380380380380380380268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268
104104104104104104104104104
432432432432432432432432432
268268268268268268268268268
432432432432432432432432432
432432432432432432432432432
432432432432432432432432432268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332400400400400400400400400400
340340340340340340340340340340340340340340340340340340
340340340340340340340340340
340340340340340340340340340
340340340340340340340340340
332332332332332332332332332
340340340340340340340340340
340340340340340340340340340
108108108108108108108108108
332332332332332332332332332
332332332332332332332332332
108108108108108108108108108
108108108108108108108108108
268268268268268268268268268116116116116116116116116116268268268268268268268268268116116116116116116116116116116116116116116116116116116504504504504504504504504504
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116268268268268268268268268268116116116116116116116116116504504504504504504504504504404040404040404040404040404040404040504504504504504504504504504132132132132132132132132132132132132132132132132132132404040404040404040
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
103
Low SINR Area 3 – Pilot Pollution [Cont.]
BestASPPN CountOfBestASPPN AvgOfAvgOfATReceivePower AvgOfAvgOfBestASPEcIo
268 27 -70.6 -5.7
432 21 -69.3 -5.6
104 4 -68.0 -7.2
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
104
Low SINR Area 4 – Pilot Pollution
2_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_500
2_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_132
2_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_352
10_1_11210_1_11210_1_11210_1_11210_1_11210_1_11210_1_11210_1_11210_1_112
10_2_10410_2_10410_2_10410_2_10410_2_10410_2_10410_2_10410_2_10410_2_104
10_3_4410_3_4410_3_4410_3_4410_3_4410_3_4410_3_4410_3_4410_3_44
31_1_23631_1_23631_1_23631_1_23631_1_23631_1_23631_1_23631_1_23631_1_236
31_3_31631_3_31631_3_31631_3_31631_3_31631_3_31631_3_31631_3_31631_3_316
38_1_45638_1_45638_1_45638_1_45638_1_45638_1_45638_1_45638_1_45638_1_456
38_2_10038_2_10038_2_10038_2_10038_2_10038_2_10038_2_10038_2_10038_2_100
38_3_17638_3_17638_3_17638_3_17638_3_17638_3_17638_3_17638_3_17638_3_176
75_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_12
75_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_108
75_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_56
88_1_5288_1_5288_1_5288_1_5288_1_5288_1_5288_1_5288_1_5288_1_52
88_2_21288_2_21288_2_21288_2_21288_2_21288_2_21288_2_21288_2_21288_2_212
88_3_30888_3_30888_3_30888_3_30888_3_30888_3_30888_3_30888_3_30888_3_308
91_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_64
91_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_116
91_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_476
100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80
100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16
100_3_492100_3_492100_3_492100_3_492100_3_492100_3_492100_3_492100_3_492100_3_492
169_2_168169_2_168169_2_168169_2_168169_2_168169_2_168169_2_168169_2_168169_2_168
169_3_128169_3_128169_3_128169_3_128169_3_128169_3_128169_3_128169_3_128169_3_128
173_1_412173_1_412173_1_412173_1_412173_1_412173_1_412173_1_412173_1_412173_1_412
173_2_156173_2_156173_2_156173_2_156173_2_156173_2_156173_2_156173_2_156173_2_156
173_3_144173_3_144173_3_144173_3_144173_3_144173_3_144173_3_144173_3_144173_3_144
183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208
183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184
183_3_196183_3_196183_3_196183_3_196183_3_196183_3_196183_3_196183_3_196183_3_196
121212121212121212
161616161616161616
161616161616161616
161616161616161616
161616161616161616
121212121212121212
565656565656565656
565656565656565656
565656565656565656
565656565656565656
565656565656565656
565656565656565656
108108108108108108108108108
108108108108108108108108108
108108108108108108108108108132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
184184184184184184184184184
104104104104104104104104104
500500500500500500500500500
176176176176176176176176176100100100100100100100100100100100100100100100100100100100100100100100100100100100492492492492492492492492492492492492492492492492492492444444444492492492492492492492492492444444444444444444444444444444444444444444444492492492492492492492492492492492492492492492492492492444444444492492492492492492492492492492492492492492492492492492492492492492492492492492492 808080808080808080808080808080808080808080808080808080808080808080808080808080808080808080
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
105
Low SINR Area 4 – Pilot Pollution [Cont.]
BestASPPN CountOfBestASPPN AvgOfAvgOfATReceivePower AvgOfAvgOfBestASPEcIo
500 17 -61.4 -5.4
104 15 -60.3 -6.2
176 14 -59.6 -5.4
184 5 -60.9 -6.9
100 3 -59.3 -6.0
All Rights Reserved © Alcatel-Lucent 2008
CL3724-SG.en.ul
106
Low SINR Area 5 – Pilot Pollution (Overshoot)
10_1_11210_1_11210_1_11210_1_11210_1_11210_1_11210_1_11210_1_11210_1_112
10_2_10410_2_10410_2_10410_2_10410_2_10410_2_10410_2_10410_2_10410_2_104
14_1_8014_1_8014_1_8014_1_8014_1_8014_1_8014_1_8014_1_8014_1_80
14_2_6014_2_6014_2_6014_2_6014_2_6014_2_6014_2_6014_2_6014_2_60
21_2_22421_2_22421_2_22421_2_22421_2_22421_2_22421_2_22421_2_22421_2_224
31_1_23631_1_23631_1_23631_1_23631_1_23631_1_23631_1_23631_1_23631_1_236
31_3_31631_3_31631_3_31631_3_31631_3_31631_3_31631_3_31631_3_31631_3_316
34_1_24434_1_24434_1_24434_1_24434_1_24434_1_24434_1_24434_1_24434_1_244
34_2_29234_2_29234_2_29234_2_29234_2_29234_2_29234_2_29234_2_29234_2_292
38_1_45638_1_45638_1_45638_1_45638_1_45638_1_45638_1_45638_1_45638_1_456
38_2_10038_2_10038_2_10038_2_10038_2_10038_2_10038_2_10038_2_10038_2_100
66_1_3266_1_3266_1_3266_1_3266_1_3266_1_3266_1_3266_1_3266_1_32
66_2_24066_2_24066_2_24066_2_24066_2_24066_2_24066_2_24066_2_24066_2_240
67_1_8867_1_8867_1_8867_1_8867_1_8867_1_8867_1_8867_1_8867_1_88
67_2_30467_2_30467_2_30467_2_30467_2_30467_2_30467_2_30467_2_30467_2_304
75_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_12
78_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_336
78_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_428
100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80100_1_80
100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16100_2_16
121_1_120121_1_120121_1_120121_1_120121_1_120121_1_120121_1_120121_1_120121_1_120
121_2_132121_2_132121_2_132121_2_132121_2_132121_2_132121_2_132121_2_132121_2_132
151_1_136151_1_136151_1_136151_1_136151_1_136151_1_136151_1_136151_1_136151_1_136
183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208183_1_208
183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184183_2_184
213_1_172213_1_172213_1_172213_1_172213_1_172213_1_172213_1_172213_1_172213_1_172
213_2_468213_2_468213_2_468213_2_468213_2_468213_2_468213_2_468213_2_468213_2_468 217_1_460217_1_460217_1_460217_1_460217_1_460217_1_460217_1_460217_1_460217_1_460
217_3_228217_3_228217_3_228217_3_228217_3_228217_3_228217_3_228217_3_228217_3_228
219_2_164219_2_164219_2_164219_2_164219_2_164219_2_164219_2_164219_2_164219_2_164
108_1_140108_1_140108_1_140108_1_140108_1_140108_1_140108_1_140108_1_140108_1_140
108_2_96108_2_96108_2_96108_2_96108_2_96108_2_96108_2_96108_2_96108_2_96
72_1_40472_1_40472_1_40472_1_40472_1_40472_1_40472_1_40472_1_40472_1_404
241_1_264241_1_264241_1_264241_1_264241_1_264241_1_264241_1_264241_1_264241_1_264
241_2_276241_2_276241_2_276241_2_276241_2_276241_2_276241_2_276241_2_276241_2_276
242_1_28242_1_28242_1_28242_1_28242_1_28242_1_28242_1_28242_1_28242_1_28
242_2_496242_2_496242_2_496242_2_496242_2_496242_2_496242_2_496242_2_496242_2_496
247_1_8247_1_8247_1_8247_1_8247_1_8247_1_8247_1_8247_1_8247_1_8
247_2_32247_2_32247_2_32247_2_32247_2_32247_2_32247_2_32247_2_32247_2_32
252_1_484252_1_484252_1_484252_1_484252_1_484252_1_484252_1_484252_1_484252_1_484
252_2_88252_2_88252_2_88252_2_88252_2_88252_2_88252_2_88252_2_88252_2_88
259_1_36259_1_36259_1_36259_1_36259_1_36259_1_36259_1_36259_1_36259_1_36
259_2_128259_2_128259_2_128259_2_128259_2_128259_2_128259_2_128259_2_128259_2_128
261_1_24261_1_24261_1_24261_1_24261_1_24261_1_24261_1_24261_1_24261_1_24
261_2_500261_2_500261_2_500261_2_500261_2_500261_2_500261_2_500261_2_500261_2_500
227_1_104227_1_104227_1_104227_1_104227_1_104227_1_104227_1_104227_1_104227_1_104
227_3_480227_3_480227_3_480227_3_480227_3_480227_3_480227_3_480227_3_480227_3_480
87_1_25687_1_25687_1_25687_1_25687_1_25687_1_25687_1_25687_1_25687_1_256
87_2_44887_2_44887_2_44887_2_44887_2_44887_2_44887_2_44887_2_44887_2_448
226_1_112226_1_112226_1_112226_1_112226_1_112226_1_112226_1_112226_1_112226_1_112
226_2_48226_2_48226_2_48226_2_48226_2_48226_2_48226_2_48226_2_48226_2_48
98_1_28498_1_28498_1_28498_1_28498_1_28498_1_28498_1_28498_1_28498_1_284
256_1_52256_1_52256_1_52256_1_52256_1_52256_1_52256_1_52256_1_52256_1_52
256_2_72256_2_72256_2_72256_2_72256_2_72256_2_72256_2_72256_2_72256_2_72
99_1_17699_1_17699_1_17699_1_17699_1_17699_1_17699_1_17699_1_17699_1_176
99_2_499_2_499_2_499_2_499_2_499_2_499_2_499_2_499_2_4
236_1_504236_1_504236_1_504236_1_504236_1_504236_1_504236_1_504236_1_504236_1_504
236_2_488236_2_488236_2_488236_2_488236_2_488236_2_488236_2_488236_2_488236_2_488
169_1_44169_1_44169_1_44169_1_44169_1_44169_1_44169_1_44169_1_44169_1_44
686868686868686868686868686868686868
686868686868686868686868686868686868686868686868686868686868686868686868686868686868686868
500500500500500500500500500500500500500500500500500500606060606060606060
500500500500500500500500500606060606060606060
500500500500500500500500500500500500500500500500500500
136136136136136136136136136136136136136136136136136136
136136136136136136136136136
136136136136136136136136136
136136136136136136136136136
808080808080808080
808080808080808080
808080808080808080
161616161616161616
161616161616161616
121212121212121212500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
100100100100100100100100100100100100100100100100100100492492492492492492492492492444444444444444444444444444492492492492492492492492492492492492492492492492492492492492492492492492492492492
Best ASP PN
(PN)
450 to 511 (410)
400 to 450 (169)
350 to 400 (139)
300 to 350 (927)
250 to 300 (235)
200 to 250 (1)
150 to 200 (23)
100 to 150 (1085)
50 to 100 (591)
0 to 50 (93)
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Low SINR Area 5 – Pilot Pollution (Overshoot) [Cont.]
BestASPPN CountOfBestASPPN AvgOfAvgOfATReceivePower AvgOfAvgOfBestASPEcIo
500 20 -52.8 -6.2
136 10 -53.9 -6.1
60 7 -51.8 -8.3
68 2 -50.8 -7.9
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2_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_5002_1_500
2_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_1322_2_132
2_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_3522_3_352
6_1_46_1_46_1_46_1_46_1_46_1_46_1_46_1_46_1_4
29_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_50429_1_504
29_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_8429_2_84
29_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_39229_3_392
36_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_34036_1_340
36_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_32436_2_324
36_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_40036_3_400
63_1_43263_1_43263_1_43263_1_43263_1_43263_1_43263_1_43263_1_43263_1_432
63_2_16463_2_16463_2_16463_2_16463_2_16463_2_16463_2_16463_2_16463_2_164
63_3_14063_3_14063_3_14063_3_14063_3_14063_3_14063_3_14063_3_14063_3_140
75_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_1275_1_12
75_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_10875_2_108
75_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_5675_3_56
78_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_33678_1_336
78_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_42878_2_428
91_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_6491_1_64
91_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_11691_2_116
91_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_47691_3_476
180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436180_1_436
180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316180_2_316
180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328180_3_328
182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332182_1_332
182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380182_2_380
182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268182_3_268
187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296187_1_296
187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376187_2_376
187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104187_3_104
121212121212121212
121212121212121212
565656565656565656
565656565656565656
565656565656565656
565656565656565656
108108108108108108108108108
108108108108108108108108108565656565656565656
565656565656565656
116116116116116116116116116565656565656565656
116116116116116116116116116
332332332332332332332332332
116116116116116116116116116116116116116116116116116116108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332108108108108108108108108108108108108108108108108108108332332332332332332332332332108108108108108108108108108332332332332332332332332332108108108108108108108108108332332332332332332332332332332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
332332332332332332332332332
436436436436436436436436436
969696969696969696
436436436436436436436436436
324324324324324324324324324332332332332332332332332332
324324324324324324324324324
436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436436380380380380380380380380380296296296296296296296296296380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380380268268268268268268268268268268268268268268268268268268268268268268268268268268268
268268268268268268268268268
268268268268268268268268268
116116116116116116116116116
432432432432432432432432432268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268268332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332332
340340340340340340340340340340340340340340340340340340332332332332332332332332332436436436436436436436436436332332332332332332332332332
340340340340340340340340340
340340340340340340340340340
332332332332332332332332332
340340340340340340340340340
108108108108108108108108108
332332332332332332332332332
108108108108108108108108108
332332332332332332332332332
116116116116116116116116116268268268268268268268268268116116116116116116116116116116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116
116116116116116116116116116504504504504504504504504504268268268268268268268268268504504504504504504504504504404040404040404040404040404040404040
504504504504504504504504504
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
132132132132132132132132132
500500500500500500500500500
500500500500500500500500500
500500500500500500500500500
Low SINR Area 6 – Pilot Pollution
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Low SINR Area 6 – Pilot Pollution [Cont.]
BestASPPN CountOfBestASPPN AvgOfAvgOfATReceivePower AvgOfAvgOfBestASPEcIo
332 84 -78.4 -6.3
436 7 -77.7 -6.3
108 4 -78.9 -5.7
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External Interference
Description
Presence of strong unintended signal impacts the ability to demodulate
desired signal
Raises noise floor at the AT/cell
Several flavors
Inband spurious transmitter - most common
Spill-over from legitimate transmission in the adjacent channel
Inadequate filter roll-offs (transmitter or receiver)
Narrow spectral spacing
Non “1-to-1 overlay” (such as, skipping over some 2G/3G1x cells when deploying
1xEVDO)
Inter-modulation products generated from strong signal on the neighboring
channel due to amplifier non-linearity at the receiver front-end
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External Interference (Cont.)
Symptoms / Identification Techniques
Detecting the presence / source is often very difficult The higher the magnitude of interference, easier to detect
Often requires shutting down 1xEVDO transmission - therefore, best to detect in pre-
commercial stages
On the reverse link, look for high levels of Short and Long Term Average RSSI Rise at relatively fewer Connection Requests
Rev Frame Error (Reverse Link Frame Error / Total Reverse Link Frame)
Total Setpoint for Reverse Outer Loop Power Control (per rate)
On the forward link, Will require drive tests in the areas with impact on KPIs
Look for high FER and/or low transmission rate in areas with high AT Rx power and low SNR,
after eliminating other factors such as, missing neighbors, search window issues, Pilot
pollution
For Inter-Mod, best course is to look for a much larger reduction in
received signal at AT / cell compared to an attenuation inserted in-line IM product attenuates at a much faster rate than the desired signal
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External Interference (Cont.)
Mitigation Strategies
In many cases, identifying an external interferer is the difficult part, fix is
relatively easy - shut off the interferer
Other sources are not easy to resolve
Narrow spacing
Change frequency planning
Skipped cell deployment
Increase channel spacing or add 1xEVDO cells to maintain one-to-one overlay
Inadequate filter roll-offs
Involves hardware change (sharper rolloffs)
IM products
Robust receiver (e.g, switchable attenuation)
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Non-optimized Neighbor Lists (NL)
Description
Neighboring sectors with sufficient strength not entered in the NL translations
Causes interference to the Active set
lower SNR/requested rates on the fwd link
higher AT power on the rev link due to “subdued” diversity
Keeps AT from tuning to a stronger Pilot in idle mode
Other NL integrity issues
Reciprocity - A is in B’s NL, but B is not in A’ NL
PN ambiguity
Cell A has X and Y on the NL, both have same PN
Cell A has X and B; neighboring cell B has Y; both X and Y have same PN
Cross face omission
Too many neighbors - pay attention to NL > 15 neighbors
AP IP address check - inconsistencies in the AP’s IP address specified for each
neighbor and the actual one
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Non-optimized NL (Cont.)
Symptoms / Identification Techniques
Scrub neighbor lists, on cells with impact on all 3 KPIs (esp. Est call rate)
Ensure recommendations are followed - include cross face and first tier inwards
facing sectors at a minimum
Use custom tools (such as, LUNAR’s NLAlert, HOM-UNL) to identify NL integrity issues
If one-to-one 2G/3G1x underlay, look for parity of NL on both
Mitigation Strategies
Fix NL issues identified above by adding neighbors or PN re-planning as the case may
be
Usually dropping NL is not a good idea unless absolutely sure and NL is getting full
For standalone 1xEVDO deployments, drive test is the best choice
Drive test with wide Remaining set srch window
Fine tune as additional system level tools (such as HO Max/UNL) become available
If performance on both 2G/3G-1x and 1xEV-DO not up to mark with similar NL
Fine tune NL using HO Max and Undeclared NL (UNL) on 2G/3G-1x
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10_1 (PN192) and
201_2 (PN231) almost at
same EcIo levels
Neighbor List - Ec/Io Levels
Street
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Service
Node ID
FMS Frame
ID
BTS
ID
Sector
ID
Neighbor
ID
Neighbor
BTS ID
Neighbor
Sector ID
Neighbor Pilot PN Offset (units of 64
PN chips)
121 20 196 1 1 10 1 192
121 20 196 1 2 10 2 195
121 20 196 1 3 191 1 318
121 20 196 1 4 194 1 309
121 20 196 1 5 196 2 384
121 20 196 1 6 196 3 387
121 20 196 1 7 201 1 228
121 20 196 1 8 201 2 231
121 20 196 1 9 202 1 138
121 20 196 1 10 203 2 375
121 20 196 1 11 203 3 378
121 20 196 1 12 203 1 372
121 20 196 1 13 205 2 222
121 20 196 1 14 205 3 225
121 20 196 1 15 206 3 135
121 20 196 1 16 208 2 42
Neighbor List - NL of 196_1 (PN381)
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Neighbor List – 3G-1X Handoff Matrix Data
NbrFMS NbrBTSId NbrSectorID HANDOFF PercHO
121_20 201 2 4903 12.52619
121_20 203 2 3782 22.18844
121_20 191 1 2854 29.47984
121_20 203 3 3173 37.58622
121_20 205 3 3112 45.53676
121_20 10 2 2918 52.99167
121_20 10 1 2768 60.06336
121_20 201 1 2201 65.68647
121_20 205 2 2318 71.6085
121_20 196 2 2364 77.64805
121_20 194 1 2274 83.45767
121_20 202 2 1471 87.21578
121_20 194 3 1292 90.51658
121_20 192 2 879 92.76225
121_20 207 3 924 95.12289
121_20 208 2 501 96.40284
121_20 206 3 265 97.07986
121_20 203 1 203 97.59849
Changes implemented:In the neighbor list of 196_1, moved 201_2 to the top of the list (nbrid #1)
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10_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_192
10_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_195
10_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_198
191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318
191_2_321191_2_321191_2_321191_2_321191_2_321191_2_321191_2_321191_2_321191_2_321
192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444
192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447
192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450
194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309
194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312
194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315
196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381
196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384
196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387
201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228
201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234
202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138
202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141
202_3_144202_3_144202_3_144202_3_144202_3_144202_3_144202_3_144202_3_144202_3_144
203_1_372203_1_372203_1_372203_1_372203_1_372203_1_372203_1_372203_1_372203_1_372
203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375
203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378
Best ASP SINR
(dB)
20 to 100 (0)
10 to 20 (87)
5 to 10 (69)
0 to 5 (122)
-5 to 0 (27)
-10 to -5 (5)
-30 to -10 (0)
Before the neighbor list of 196_1 ASP SINR
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10_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_192
10_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_195
10_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_198
191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318
192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444
192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447
192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450
194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309
194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312
194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315
196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381
196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384
196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387
201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228
201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234
202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138
202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141
203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375
203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378
Best ASP SINR
(dB)
20 to 100 (0)
10 to 20 (137)
5 to 10 (66)
0 to 5 (121)
-5 to 0 (21)
-10 to -5 (0)
-30 to -10 (0)
After the neighbor list changes on sector 196_1 ASP SINR
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10_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_19210_1_192
10_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_19510_2_195
10_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_19810_3_198
191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318191_1_318
192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444192_1_444
192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447192_2_447
192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450192_3_450
194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309194_1_309
194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312194_2_312
194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315194_3_315
196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381196_1_381
196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384196_2_384
196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387196_3_387
201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228201_1_228
201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_2_231201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234201_3_234
202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138202_1_138
202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141202_2_141
203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375203_2_375
203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378203_3_378
RLP Throughput - Forward
(kbps)
2,000 to 2,500 (0)
1,300 to 2,000 (0)
1,000 to 1,300 (0)
320 to 1,000 (268)
80 to 320 (34)
1 to 80 (4)
0 to 1 (0)
Before RLP Throughput
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After: RLP Throughput –Fwd at Metric Blvd
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Inadequate Search Window Size
Pilot A
at cell
Earliest arrival of
pilot A at AT
PN Phase
PN Phase
BS A transmitting
pilot A
(reference pilot)
AT, looking
for an Active Set pilot
AT, looking for a
Neighbor or
Remaining Set pilotPN Phase
Pilot B at BS
AT assumes pilot B is (B - A) * 64 chips away
from the earliest arrival of the reference pilot.
Pilot B is (B - A) * 64 chips away
PN Phase
Earliest arrival of
pilot B at AT
Neighbor SetSearch Window
Active SetSearch Window
BS B transmitting
pilot B
Strong multi-path Spreading delay !
Useful PNs can be left out !
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Inadequate Search Window Size (Cont.)
Symptoms / Identification Techniques
Best detected via drive tests
First eliminate issues with coverage/ non-optimized neighbor list
On the forward link, often symptoms similar to those from external
interference
Good AT receive power, but poor SNR
Pilot scanner helps in case of 2G/3G1x, no such tool available yet for 1xEVDO
Data from one-to-one 2G/3G1x underlay will help
LUNAR can help warn potential need for larger size if phase for a particular
Active/Neighbor pilot in a Route Update Message is at edge of the window
However, can’t alarm if Pilot is not reported in RUM at all
Mitigation Strategies
Increase the neighbor list search window size by one step until AT is able
to detect the Pilot
1xEVDO allows Neighbor set search window size to be specified per pilot
If a distant overshooting Pilot, try containing its coverage via down tilt
or CBR attenuation or use if not able to contain
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Mobile Search Window Considerations
Delay
Spread
Pilo
t C
ha
nn
el R
ela
tive
Str
en
gth
64lN Chips
Correlation Time in Chips
PoP2 P3
P3
P2P1
Po
P1At the BS
Transmitter
At the MS
Rake Receiver
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Mobile Search Window Considerations
A
D1
D2B
Minimum neighbor search window in chips is:
2 x (D2 - D1) x 6.6 + 2 x largest delay spread / Tc
Where:
• D1 and D2 are in miles
• 6.6 chips = 1 mile
• Delay spread
Urban 7 microseconds
Suburban 2 microsecondsNote: 1 / (light x Tc) = 6.6
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Cell Search Window Considerations
Time in PN Chips
Delay
Spread
Td,A
SRCH_WIN_A
Rela
tive
Ec/I
oo
f
Mu
ltip
ath
Sig
na
ls
And Cell Search Window
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Access Search Window
Tx_delay
Rx_delay
GPS
time
Frame
Boundary
At RLM
Cell
Mobile
Mobile assumed
Time reference
Frame boundary at mobile
Delay
Delay
Earliest PN Offset,
Receive frame boundary
Access Search Window with start point at Rx_delay and width =
2 * sector_size * 6.6
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Improper PN Planning
Cell 11
Cell 10
Cell 13
Cell 12•PN10
•PN10
•PN11
Masquerading
Two Sectors
Same PN
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Improper PN planning (Cont.)
Symptoms / Identification Techniques
NL integrity tools can detect certain problems with inadequate PN reuse
margin
Other ones may be more difficult to detect, will require drive tests Look for areas with high Fwd packet error rate, but good SNR
Often may require turning off close in cell to see if SNR still remains good, and eliminating
other problem sources (hardware/software, other NL / search window integrity issues)
If SNR continues to remain strong, then look for distant overshooting cell or cell with
inadequate PN reuse margin
Requires good understanding of terrain to identify potential interfering cell
Mitigation Strategies
After identifying the distant problem cell, try containing its coverage
using downtilt/CBR
Inadequate PN reuse margin case will require PN re-planning / Pilot
Increment adjustments A good idea to pay more attention upfront in the design stage
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RNC Border Issues
RNC 1 RNC 2 RNC 3
Border Border
IP IP
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Inter-RNC Border Issues (Cont.)
Symptoms / Identification Techniques
Chances of high Inter-RNC Handoff Failures degrading Call Drop Rate
Inter-RNC Handoff Method
IP connectivity between the RNCs
Call Processing Codes
10007, 10008, 13005, 13006
Refer to Inter-RNC Idle Handoff Metrics in the KPI section
High occupancy of Access Channel
Established Connection Rate metric and the AT/AN initiated connection attempt failure rate is degraded.
Reduced Data Throughput in and Inter-RNC Active Handoff due to latency between the RNCs involved in the connection
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Inter-RNC Border Issues (Cont.)
Mitigation Strategies
Define RNC border in low data usage areas
New ATs (MSM5500 vs MSM6500 or MSM6800)
Inter-RNC delay (one-way) be less than 25ms to avert performance issues associated with Inter-RNC active handoffs
Change the Inter-RNC Handoff Method to Color Code
Avoid RNC border that runs parallel to major highways/roads
Avoid RNC borders near major office buildings, water bodies and island cells (a few cells in a RNC surrounded by cells on a different RNC)
If a new RNC is needed in heavy usage area (capacity need), instead of adding new cells on to a new RNC, re-distribute cells evenly across RNCs
RNC grouping feature
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Access Terminal’s Ping-Pong Behavior at RNC Boundary –MSM5500 v/s MSM6500(6800)
AT’s ping-pong problem
A dormant AT stationed at RNC boundaries may perform Idle Handoffs back-and-forth
ATs based on MSM6500 chipset uses additional margin for Idle Handoffs to reduce the ping-pong effect and thereby possibly reducing Idle Handoff attempts and failure rate
For example, if AT performs Intra-RNC Idle Handoff when the Pilot strength of the target sector is D dB stronger than the current Pilot in the active set, then MSM6500 based AT performs Inter-RNC Idle Handoff when the Pilot strength of the target sector is (D+d) dB stronger than the current Pilot in the active set, d > 0
The additional margin of d dB is not used for the first Inter-RNC Idle handoff attempt since AT doesn’t know that this Pilot is from a different Color Code
The value of d may not be fixed. At low values of Ec/Io, the margin d may be reduced
MSM5500 AT uses the Pilot strength differential of D dB for both Intra and Inter-RNC Idle Handoffs
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Chester’s (MSM5500) Ping-Pong Behavior – Lab Results
Best Active Set Pilot (ASP) PN – Best
Active Set Pilot PN that the AT is
currently Idling on
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LGVX8000 (MSM6500) Ping-Pong Behavior – Lab Results
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AirPrime (MSM5500) versus LGVX8000 (MSM6500) – Field Results
0
1
Tim
esta
mpD
T
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
02/1
8/2
005
AirPrime
LG
4 Pilots, 2 from each RNC; 0 and 1 represent two different RNCs
Field data above indicates reduction of about 20% to 25% in AT ping-ponging with
MSM6500 chipset
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RNC Grouping Overview
Allows multiple RNCs to form a group in which the AT can be served by one RNC but controlled by another RNC in the group
Provides the capability so that the AT does not have to register when crossing an RNC boundary. If the group is configured so the AT does register when it crosses an RNC boundary, the AT is able to keep the same session.
Improves the overall system performance by avoiding the idle handoff ping ponging and RATI ping-ponging at RNC boundaries.
The PCF entity with the A10 termination sends page messages across RNC boundaries to any cell within the group.
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RNC Grouping Overview (cont.)
Max. 63 RNC members/Group, 6 Groups/Service Node (SN)
Subnet mask is (automatically) changed to 70 (from 104) when that RNC is added to a Group. RNC group member creation uses data from ColorCodeMap table
When changing Color Code or AN IP address in the ColorCodeMap table, the corresponding RNC member is deleted and re-added to the group.
Add or Delete of a RNC to a RNC group will force all ATs within the group to reregister
Subnet Mask=70
AT requests Idle Handoff between RNCs in a group. Same UATI is re-assigned unless session is transferred. AT requests Prior Session Handoff between RNCs in a group
Subnet Mask=64
AT doesn’t request Idle Handoff and Prior Session Handoff between RNCs in a group
No session transfer between RNC members in the same group unless Load Balance criteria is met (For Subnet Mask=70)
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RNC Grouping Overview (cont.)
Load Balancing
When AT moved between members in the same group, and when UATI req is received and serving RNC is different from the controlling RNC or Last Seen RNC, the controlling RNC will perform Load Balancing and determine if the session should be transfer to the serving RNC.
The Criteria for Load Balancing is as follows:
L=no of sessions * 100 / Max no of sessions
L_cont > Session Load Threshold
L_cont > L_serv + Session Load Differential
Controlling RNC completed the session parameter negotiation
No Traffic Channel is in the progress of being setup
No EIS message begin deferred
No paging for the AT in progress
When session not transferred, the Cont RNC assign the same UATI back to the AT. If the session is transferred, the new Cont RNC assign the new UATI
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RNC Grouping Overview (cont.)
Subnet mask included in the SectorParameters message is used as a bit mask by the AT to ignore certain bits of the SectorID field in the SectorParameters message
Subnet Mask=70
Both Member ID and Group ID are parsed by the AT, forcing it to re-register
(UATIRequest) when moving across RNC boundaries within the RNC group (still
keeps same UATI). This will allow load balancing across RNC group members.
l Subnet Mask=64
The member ID is not parsed by the AT, and hence won’t be forced to re-
register (UATIRequest) when moving across RNC boundaries within the RNC
group. This implies RNC group members won’t perform session load balancing
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RNC Grouping Overview (cont.)
Sector ID
Sector ID Provisioning is always turn on
Sector ID will also include Sector ID Version, RNC Group ID, RNC Member ID. These will be “0” if the RNC is not in a Group
Sector ID Version Included can be set to yes or no. If set to no, Sector ID version will be “0”
Sector ID Version is sync across all the RNCs in the same group
AT will re-register (UATI Req) when Sector ID version is changed (when Sector ID included flag is set to yes)
Sector ID version will be incremented if the following occurs
RNC is added or removed from the group, including changes due to CCMap changes
RNC member in the group is rebooted or goes down or lost communication
There is a OHM Session Lost (eg. both pri/bkup OHM failed)
Sector ID parameters is changed
There is a communication lost between members in the RNC in the same group
Subnet Mask changed
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Paging with RNC Grouping
Paging algorithm without RNC Grouping:
Page Last Active Set a given number (translation parameter) of times
If no response, send Page message to the entire RNC
If still no response, A10 data that triggered Page is discarded
New Paging Algorithm with RNC Grouping:
Page last active set (same as before)
No response, send Page to Last Seen RNC
No response, send Page to Neighbor RNCs within group (Last two seen RNCs)
No response, send Page to the entire RNC Group
If still no response, A10 data that triggered Page is discarded
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Enabling/disabling RNC Grouping
The CCMap Table needs to be provisioned correctly for including a RNC into a Group
Neighboring RNCs, not in the group, need to have their CCMap table populated for all RNCs within the group and not just the geographically adjacent RNCs within the group
Create RNC Group(s) on the respective SN
Add or remove RNC to the Group to enable/disable RNC Grouping
Modify Subnet Mask between 70 and 64 when the RNC is in a group
Subnet Mask parameter is updateable with both RNC and Cell loads
Set SectorID Version Included flag to Yes
SectorID Provisioning will always be ON
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RNC Grouping in OMC-RAN
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RNC Grouping in OMC-RAN (contd.)
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RNC Grouping in OMC-RAN (contd.)
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RNC Grouping in OMC-RAN (contd.)
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RNC Grouping in OMC-RAN (contd.)
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Hardware Issues
Description Faulty hardware impacting call quality
Such as, bad filter, channel card (EVM), CBR/UCR, T1/E1, antenna connection issues, drifts in timing circuitry (island mode problem)
Any h/w issues at FMS will have broader impact (multiple cells), so easier to detect
Symptoms / Identification Techniques
Correlated degradation in several metrics
Always look for unusual alarms first
Currently ROP supports alarming for AP, TP and cell issues
RF hardware issues, if not caught by alarms, become more apparent with drive tests
Low mobile rx power, high mobile transmit power
In some cases, Established call rate looks nominal, but most call attempts don’t even go through (cell cannot hear the mobile )
Isolating the fault device may require replacing several h/w devices in the chain
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Hardware Issues (Cont.)
Mitigation Strategies
Detection is the more difficult part, esp. for intermittent mal-functions; resolution is easy
First verify if software restore/ fresh install / hardware reseating clears out the problem
Otherwise, replace the faulty device
Escalate to development
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Authentication Failures
Description
There are two stages of authentication During new session establishment via AAA - does not impact any KPIs on the RAN since it is
performed after establishing traffic channel
During successive reactivations from dormancy
Symptoms / Identification Techniques
Host of counts for the latter type of failure Number of Security Protocol Negotiation Failures
Number of Session Key Length Negotiation Failures
Number of key Response message timeouts
Number of Session Security Digest Mismatches
Number of Session Security ATKeyComplete message time-outs
Number of packet discards in SHA-1 Authentication Protocol
Number of Authentication Failures for postponed Security packets on old 1XEV_call Control
Number of authentication failures for postponed security packets on new 1XEV-Call Control
Number of Encryption Attribute negotiation failures
Pegged at the TP level
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Authentication Failures (Cont.)
Mitigation Strategies
If the number of authentication failures of the latter type is unacceptably high, first course of action should be to verify software / configuration issues
Given early in the 1xEVDO deployment cycle, will require development support to troubleshoot and resolve
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High Forward Link Traffic Loading
Description
Higher demand than the available RF bandwidth (assume sufficient cell/network resources)
Per user throughput / end-user experience suffers due to fewer time-slots per user
Symptoms / Identification Techniques
In the data world, divergence between requested and assigned rates often used as indicator of congestion
Difference between Requested DRC rates and Total Packets Transmitted on the Forward link (weighted average over different rates for each) may be used
Lower RLP Octets Transmitted on the Forward Link / Established Call is another indicator
Need calibration with real field data to model
Ensure peak Sector Throughput is not sacrificed
Otherwise may suggest other issues (hardware, interference, optimization, etc.)
Mitigation Strategies
Investigate potential for RF optimization (coverage, pilot pollution, NL/srch win issues, etc)
Add a carrier
Add a cell to serve heavy traffic area
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High Forward Link Traffic Loading
FL Time Slot Busy %
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
10
/16
/20
06
1:0
0
10
/16
/20
06
6:0
0
10
/16
/20
06
11
:00
10
/16
/20
06
16
:00
10
/16
/20
06
21
:00
10
/17
/20
06
3:0
0
10
/17
/20
06
8:0
0
10
/17
/20
06
13
:00
10
/17
/20
06
18
:00
10
/17
/20
06
23
:00
10
/18
/20
06
5:0
0
10
/18
/20
06
10
:00
10
/18
/20
06
15
:00
10
/18
/20
06
20
:00
10
/19
/20
06
2:0
0
10
/19
/20
06
7:0
0
10
/19
/20
06
12
:00
10
/19
/20
06
17
:00
10
/19
/20
06
22
:00
10
/20
/20
06
4:0
0
10
/20
/20
06
9:0
0
10
/20
/20
06
14
:00
10
/20
/20
06
19
:00
317/1
317/2
317/3
Engineering Limit
Per User Throughput FL (kbps)
0.0
100.0
200.0
300.0
400.0
500.0
600.0
700.0
800.0
900.0
1000.0
10
/16
/20
06
1:0
0
10
/16
/20
06
6:0
0
10
/16
/20
06
11
:00
10
/16
/20
06
16
:00
10
/16
/20
06
21
:00
10
/17
/20
06
3:0
0
10
/17
/20
06
8:0
0
10
/17
/20
06
13
:00
10
/17
/20
06
18
:00
10
/17
/20
06
23
:00
10
/18
/20
06
5:0
0
10
/18
/20
06
10
:00
10
/18
/20
06
15
:00
10
/18
/20
06
20
:00
10
/19
/20
06
2:0
0
10
/19
/20
06
7:0
0
10
/19
/20
06
12
:00
10
/19
/20
06
17
:00
10
/19
/20
06
22
:00
10
/20
/20
06
4:0
0
10
/20
/20
06
9:0
0
10
/20
/20
06
14
:00
10
/20
/20
06
19
:00
317/1
317/2
317/3
FLTS% = EVM_TOTAL_BUSY_PCNT_SLOTS/10E6
RLP_TXED_FTC/10E3*8/3600 / (EVM_ACTIVE_USAGE / 2160000)
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Heavy Reverse Link Traffic Loading
Description
High reverse link traffic shrinks reduce footprint, so it impacts ATs at edge of coverage
Contributes to higher rev noise floor => higher AT transmit power => AT senses smaller head room to the max transmit power => lowers reverse transmit rates
Impact on Established Connection rate (if cell is not able to detect probes) and Data Rate Throughput
Symptoms / Identification Techniques
Look for correlated increase in several metrics High Short and Long Term Average/Peak RSSI Rise, High RFER
Higher average Eb/No setpoint (ratio of Total Setpoint for Reverse Outer Loop Control and Total Number of Frames for Reverse Outer Loop Control )
Increase in Number of Connections Force Released
High AT/AN Initiated Connection Requests
Eliminate other potential sources with similar impact External Interference
Faulty hardware (Filter, improper antenna cabling, diversity incapacitation in the CBR/UCR)
…. By verifying the degradation occurs only at high traffic
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Heavy Reverse Link Traffic Loading (Cont.)
Mitigation Strategies
Several options depending on near term deployment/growth plans
Possible order to follow
Lower reverse overload control thresholds to lower transmission rate - to preserve coverage
Increase Pilot overlap (HO region) to mitigate AT transmit power - beware of impact on forward link throughput performance
Add a carrier
Add a cell - ensure proper optimization is performed to reduce overlap
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High Reverse Link Traffic Loading
Avg Active Connections per Sector/Carrier
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
10
/16
/20
06
1:0
0
10
/16
/20
06
6:0
0
10
/16
/20
06
11
:00
10
/16
/20
06
16
:00
10
/16
/20
06
21
:00
10
/17
/20
06
3:0
0
10
/17
/20
06
8:0
0
10
/17
/20
06
13
:00
10
/17
/20
06
18
:00
10
/17
/20
06
23
:00
10
/18
/20
06
5:0
0
10
/18
/20
06
10
:00
10
/18
/20
06
15
:00
10
/18
/20
06
20
:00
10
/19
/20
06
2:0
0
10
/19
/20
06
7:0
0
10
/19
/20
06
12
:00
10
/19
/20
06
17
:00
10
/19
/20
06
22
:00
10
/20
/20
06
4:0
0
10
/20
/20
06
9:0
0
10
/20
/20
06
14
:00
10
/20
/20
06
19
:00
317/1
317/2
317/3
Engineering Limit
PEAK_ACTIVE_CONN_PER_SECTOR
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
10
/16
/20
06
1:0
0
10
/16
/20
06
6:0
0
10
/16
/20
06
11
:00
10
/16
/20
06
16
:00
10
/16
/20
06
21
:00
10
/17
/20
06
3:0
0
10
/17
/20
06
8:0
0
10
/17
/20
06
13
:00
10
/17
/20
06
18
:00
10
/17
/20
06
23
:00
10
/18
/20
06
5:0
0
10
/18
/20
06
10
:00
10
/18
/20
06
15
:00
10
/18
/20
06
20
:00
10
/19
/20
06
2:0
0
10
/19
/20
06
7:0
0
10
/19
/20
06
12
:00
10
/19
/20
06
17
:00
10
/19
/20
06
22
:00
10
/20
/20
06
4:0
0
10
/20
/20
06
9:0
0
10
/20
/20
06
14
:00
10
/20
/20
06
19
:00
317/1
317/2
317/3
Engineering Limit
Avg RSSI Rise
0
2
4
6
8
10
12
14
10
/16
/20
06
1:0
0
10
/16
/20
06
6:0
0
10
/16
/20
06
11
:00
10
/16
/20
06
16
:00
10
/16
/20
06
21
:00
10
/17
/20
06
3:0
0
10
/17
/20
06
8:0
0
10
/17
/20
06
13
:00
10
/17
/20
06
18
:00
10
/17
/20
06
23
:00
10
/18
/20
06
5:0
0
10
/18
/20
06
10
:00
10
/18
/20
06
15
:00
10
/18
/20
06
20
:00
10
/19
/20
06
2:0
0
10
/19
/20
06
7:0
0
10
/19
/20
06
12
:00
10
/19
/20
06
17
:00
10
/19
/20
06
22
:00
10
/20
/20
06
4:0
0
10
/20
/20
06
9:0
0
10
/20
/20
06
14
:00
10
/20
/20
06
19
:00
317/1
317/2
317/3
Engineering Limit
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Reverse Link Load Control
Rev A relies on the generation of the Reverse Activity Bit (RAB) to
control reverse link loading. The RAB bit:
Identifies sector loading trends and determines when flow reduction is
required
Indicates when the cell load increases above a Rise over Thermal
(RoT) target value
In Rev 0, each sector in the AT active set transmits an RAB once
during every 26.67-ms frame (37.5 times a second).
In Rev A, each sector in the AT active set transmits an RAB once
every 1.667-ms slot (600 times a second).
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Reverse Overload Control
Translation Parameter HROC Enable Flag (for CSM6800 Modem):Current Recommendation: On_Chip_RoC with LNFFNew Recommendation: On_Chip_RoC with SINF with Reverse Link Silence Duration of 1 frame and Reverse Link Silence Period of 1 frame
Both Reverse Link Silence Duration and Reverse Link Silence Periodrequire SVEBM reboot as well
It is recommended to change Reverse Link Silence Duration and Reverse Link Silence Period to 1 and 1 respectively before changing the HROC mode from LNFF to SINF. This is to ensure that SBEVM does not fails to initialize if both Duration/Period and mode are changed simultaneously
Will require two evc down/up (one for Duration/Period and another for mode) to update HROC mode from LNFF to SINF
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Reverse Overload Control (contd.)
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Rise over Thermal (RoT) Target Value
The RAB bit is
generated as a
function of a target
Rise over Thermal
(RoT) value. RAB=1RAB=1
On_chip_RAB_thresholdOn_chip_RAB_threshold
RAB=0RAB=0
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On-Chip Reverse Link Overload Control
SN General – General 2
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Congestion Overload Control (COC)
Normal Block Mute
COC Metric
Exit_Block_Thresh Enter_Block_Thresh Call_Mute_Thresh
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Basic COC Mechanism
Number of RAB=1 in RAB history used as COC metric
COC should trigger when all the existing calls are transmitting at the lowest rate
_ ROC had sufficient time to force active ATs to lowest rate via RAB
Block new (Rev 0/A) calls first then mute Rev 0 and Rev A BE (R28) calls_ COC metric is compared against call block and call mute thresholds_ Required to ensure system stability
Quickly mute large number of call (half of active calls), then slowly get them back in
_ Release the load quickly and efficiently.
Mute calls via Broadcast Reverse Rate Limit message_ BRRL transmitted every 8 Sync CC (3.4s). During block/mute state, BRRL is send every 16 frames (427ms; configurable) via Async CC_ Rev A BE flows are muted in via Grant message
If COC is triggered by external interference, then mobiles may be muted for an extended period of time depending on the level of interference
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COC States with QoS Disabled
Rev. A will treat the different flowsRelative to their QoS !
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COC States (contd.)
Normal State• In this state COC metric is continuously updated (every frame) and compared against Enter Block Threshold• If >= the block threshold, COC enters Call Block state. New calls (Rev 0 and Rev A) are blocked. Soft/Softer handoffs are allowed
Block State• In this state COC metric is compared (every 16 frames) against Exit Block Threshold and Enter Mute Threshold
COC state is re-evaluated every congestCheckPeriod (configurable; tunable parameter; default value 16 frames)View – Per Sector-Carrier,RNC; Max Value – 63 frames
• Block state will at least last 16 frames• If < below the exit block threshold, return to normal state• If >= call mute threshold, enter Mute state
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COC States (contd.)
Mute State• In this state, ½ of the total active Rev 0 / Rev A BE callswill be muted first via BRRL message (rate limit = 0) andGrant Message, respectively
• In this state COC metric is compared (every 16 frames)against Enter Mute Threshold
• If < mute threshold, the number of calls to be muted will be reduced by 1/16 of the total active Rev 0 / Rev A BE calls
Will take about 3.4 secs to exit the mute state if COC metric < mute threshold
• If >= mute threshold, ½ of the remaining un-muted Rev0 / Rev A BE calls will be muted
When the remaining un-muted Rev 0 / Rev A BE calls are less than 1/8 of the total Rev 0 / Rev A BE active calls, all of them will be muted
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Translation Parameters: Recommended Values
Call Mute RAB Pct
Service Node / Sector Carrier
1.1 -> disable
Enter Block RAB Pct
Service Category Reverse Link Congestion Overload Control
1.1 -> disable
Exit Block RAB Pct
Service Category Reverse Link Congestion Overload Control
Recommended value 0.75
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TP Overload
Description
When the processor occupancy reaches certain threshold on both the TPs under an AP, new session requests arriving at that AP are blocked
Deficit between Connection Request and Traffic channel Assigned
Tunable threshold called “TP Utilization Threshold” (currently 85%)
Safeguard mechanism to maintain performance (minimize packet drops, delays, etc.)
Symptoms / Identification Techniques
Direct count called Number of Sessions Denied due to TP in overload
Proactively monitor per-TP counts to preempt potential TP overload
TP processor occupancy
Packet drop rate (Ratio of Number of dropped packets to Packet Arrival rate )
Mitigation Strategies
Follow Alcatel-Lucent recommended Network Engineering Guidelines for 1xEVDO
Hardware/Software upgrade/ features may increase processor occupancy over time (UTP)
Can allocate fewer BTS per AP/TP assembly to alleviate traffic handled
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Maximum Number of Connections Reached
Description
Max # of users per cellsite controlled via several means
ASIC limitation
Max number of users translation (one for Rev. 0 and another for Rev. A)
Available Mac Indices for traffic channels
When either of the limit is reached, the “blocking” sector is omitted in the TCA for new calls
If all legs on the Connection Request message are “blocking”, the calls are denied Traffic Channel - impact on Established Call rate
Note each sector always tries to force release users nearing dormancy when the max users reached
Longest idling user gets released first, and so on
In order to be released, must have been inactive for > t_force_release ( 2 sec)
Even if the call is setup on a weaker cell, potential impact on Established Call rate
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Maximum Number of Connections Reached (Cont.)
Symptoms / Identification Techniques
Several SM counts can be used to identify call blocking scenario
AT/AN Initiated Connection Attempt Failures - No Resources Available
SM count to peg Max Number of Connections Reached on each blocking sector
Does not mean the call was blocked, but good precursor
Number of connections force released
Correlate with Average Active Connections per sector
Mitigation Strategies
Check coverage of the impacted/vicinity cells
Reduce coverage to offload traffic to neighboring cells if adequate room
Active Softslope Handoff Algorithm
Add carrier
If Number of carriers is exhausted, add a cell to reduce traffic demand/cell in the area
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Maximum Number of Legs Reached
Description
Handoff add is prevented if call already at max allowed number of Active set legs
Controlled by translation - Maximum Legs in Handoff - recommendation is 4
Potential impact on Drop call rate and Throughput (either link) due to handoff failures
Symptoms / Identification Techniques
Usually max legs of 4 are adequate in most environments
But impact possible in heavily pilot polluted areas especially without soft swap support
Mitigated with current capability of multiple add and drop
Direct count: Soft and Softer handoff attempts not processed – Maximum number of Legs Reached
KPI impact on neighboring sectors
Mitigation Strategies
Attempt to mitigate pilot pollution with traditional RF optimization techniques
In the short term, can try increasing the Maximum Legs in Handoff
Try 5 first; use 6 as last resort - Beware of other trade-offs (Max MAC indices, max number of connections reached, etc.)
Alternative is to expedite handoff drop conditions - lower Drop Timer translation
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No Resources at the Candidate Leg
Description
Handoff add is prevented if the candidate leg does not have resources to support the traffic channel
Could be due to insufficient Reverse Channel Resources or MAC Indices
Note that Max number of Connections only blocks new calls, not handoffs
Potential impact on Drop Call Rate and Data Throughput (either link) due to handoff failures
Symptoms / Identification Techniques
Direct count : Soft and softer handoff failures – lack of resources in the candidate sector
KPI impact on neighboring sectors
Mitigation Strategies
Check coverage of the impacted/vicinity cells
Reduce coverage to offload traffic to neighboring cells if adequate room
Add carrier
Add a cell (longer lead time) to reduce traffic demand per cell in the area
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Backhaul Restrictions
Description
Alcatel-Lucent utilizes un-channelized or raw T1/E1 backhaul for 1xEVDO between BTS and FMS No packet pipe concept unlike 2G/3G1x
Good throughput performance requires adequate backhaul (T1/E1) provisioning
A backhaul provisioning example Each T1/E1 can deliver ~1100/~1400 kbps at the RLP layer for a 3-sector cell
2 T1/E1s per cell can support an average of 680/780 kbps RLP layer throughput per sectorassuming dual antenna ATs
Enough to support 80/ 92% of typical sector throughput of 850kbps required to serve dual antenna ATs
Traffic may not be uniform across sectors, so 2T1/E1 adequate for 850kbps capacity
Above numbers apply to forward link Each T1/E1 is symmetrical
1xEVDO reverse link sector throughput much smaller and uses only one of the 2 T1/E1s
Refer to Alcatel-Lucent recommended Network Engineering Guidelines for 1xEVDO
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Backhaul Restrictions (Cont.)
Symptoms / Identification Techniques
No direct indication in SM, but always a good idea to check backhaul provisioning when investigating a low throughput cell
Also, look for alarms to isolate out of service T1/E1 line, transmission line errors or termination equipment
High Packet loss / Latency - “Dirty T1” Ping from AT/client to server under benign RF
Ping from RNC to LIU/FLM
Often issues with only 1 T1 on multi-T1 cell
Load balancing across multiple T1s on a cell (forward link) Bytes should be balanced across T1s (not # of packets)
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Backhaul Restrictions (Cont.)
Mitigation Strategies
Rectify any hardware issues found with the backhaul
Alcatel-Lucent equipment
Escalation to third party for issues with the leased line
If backhaul is not enough to support demanded traffic, indicate need for additional T1/E1 to the operator
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Hybrid Mode
•EV-DO •3G-1X
EV-DO Borders outside the blue region
Hybrid Operation inside the blue region •Hybrid Handoff
• Description
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Hybrid Handoff Failures Examples
Hybrid handoff is considered successful when the AT closes the EV-DO connection and
originates a call on 3G1x.
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Hybrid Mode (Cont.)
Symptoms / Identification Techniques
Primary cause for failure will likely be the connection attempt failures due to no traffic channel complete received from the AT
Degradation of Established Connection Rate
At the Coverage Edge, check for high AT_INIT_CONN_REQ_POOR_RF_ALLOW_SESS and AT_INIT_CONN_REQ_POOR_RF_DENY_SESS counts
Handoffs to 3G1x can be identified by looking for high number of Normal AT Connection Release relative to rest of the release counts (dominated typically by Dormancy Timer expiration).
High RF Link Lost tuneaway counts
New peg count to try to characterize the Inter-technology hand offs.
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Hybrid Mode (cont.)
Mitigation Strategies
Newer Chipsets (MSM6500 or MSM6800)
Recommend using higher SCI to alleviate throughput impact
SCI=2 a good balance between 1xEVDO throughput performance and call setup delays on 3G1x
Ensure 1xEVDO has good coverage throughout the core area to minimize handoffs to 3G1x
Active the Session Deny Thresholds on technology borders or sectors with marginal EV-DO coverage on the GUI
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Mobile IP (MIP) Mode
Description Mode that allows AT to roam from one network to another while
maintaining network connections by retaining IP address
Simple IP requires change of IP address adding to the handoff delays at network boundaries
Facilitates 1xEVDO to 3G1x handoff without session tear-downs
Transparent to RAN; but impact on
AT - maintains dual stacks and performs additional processing to preserve transparency at client
Network components - use of Home Agent and Foreign Agent
Reduces Data throughput (either link)
Higher processing burden on the AT
1xEVDO to 3G1x handoff at low SNR
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Mobile IP (MIP) Mode (Cont.)
Symptoms / Identification Techniques
Look for possibility of MIP handoffs to 3G1x in core 1xEVDO coverage area On 1xEVDO, pegged as Normal release
No SM on 3G1x to identify this
Faster Qualcomm chipsets (MSM6500/MSM6800) minimize throughput loss
Pay special attention to performance of new commercial ATs via controlled tests
Mitigation Strategies
Ensure good coverage on 1xEVDO to minimize MIP handoffs to 3G1x in the core area
Ensure software (PPP) compression parity between 1xEVDO and 3G1x configuration
If enabled on one side and disabled on the other, potential handoff issues
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AAA
IP Network Issues
FABTS
AT
RLPPCF
Call
Co
ntr
ol
1xEV Controller
Fra
me
Sele
ct
BTS
BTS
AT
AT Other
1xEV Controllers
and Routers
Other
PDSNs
o
o
o
o
o
o
o
o
Other
ATs
Other
ATs
NMS
backhaulRouter
Laptop
card, PDA,
mobile etc.
Interface between
AT and rest of the
system
interface, and buffers data to the
Performs call control, frame
selection and RLP processing.
PCF connects to PDSN over R-P
interface, and buffers data to the
user.
OA&M functions
for 1xEV-DO RAN.
Maintains link (PPP)
with AT. Maps AT to
the IP address.
Performs authentication,
authorization, and
accounting functions.
¤2 - 2
HA
AAA
internet1
2
34
5
6 7 8
9 10 11
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IP Network Issues - RNC
Improper configuration of RNC elements can impact throughput performance
Maintain/verify proper IP connectivity across various IP elements Within the RNC
RNC to cell
Cell to PDSN
Use of high bandwidth ping to isolate bottlenecks
Duplicate IP address assignments can lead to high packet loss/latency
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IP Network Issues - Improper Router Settings
Imbalanced Throughput between Carriers
Same number of users, same RF conditions on both channels?
The router was missing the IP addresses of the T1s serving FLM2 !!!!
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IP Network Issues - PDSN
Beware of any mismatches in the RNC to PDSN ethernet interface configuration
Line mode: Full duplex, Half duplex, Auto Config
Line Speed: 10Mbps, 100 mbps, Auto Detect
Mismatch between two endpoints will cause collisions, packet drops and/or large variations in latency
Becomes more apparent with multiple users
E.g., Full duplex on one side / Auto-config on the other side
Applies to any intervening switches/router between the PDSN and the RNC
Allocate adequate bandwidth between RNC and PDSN
Pipe big enough to support DO traffic and also 1x Data traffic, if sharing the PDSN
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Core Network – delay and packet loss
2.4 Mbps RF channel
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
% PER
FT
P T
hro
ug
hp
ut
(Kb
ps)
0 ms delay
50 ms delay
250 ms delay
2.4 Mbps RF channel
0
100
200
300
400
500
600
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
% PER
WE
B T
hro
ug
hp
ut
(Kb
ps)
0 ms delay 50 ms delay
250 ms delay
6 & 16 ms
delay data
points
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EV-DO Protocol Stack End to End
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TCP Layer (1)
TCP throughput time series
For both downlink and uplink, at both server and client
ppp-server
commview-client
Throughput drops,
usually a problem
indicator
HTTP
FTP
Upload
FTP
Download HTTP
FTP
Upload
FTP
Download
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TCP Layer (2)
TCP round-trip time (RTT)
For download RTT, server trace is used. For upload RTT, client trace is used.
Download RTT Upload RTT
HTTP
FTP
UploadFTP
Download
HTTP
Latency spikes,
usually a problem indicator
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TCP Layer (3)
TCP events:
TCP timeout, TCP out-of-sequence, TCP checksum error, and TCP reset
TCP timeout and out-of-
sequence,
usually an indication of packet
loss.
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TCP Layer (4)
TCP outstanding window
For download, server trace is used. For upload, client trace is used.
Shows
• TCP window size;
• TCP congestion control
events, such as slow start,
congestion avoidance, fast
retransmit and fast
recovery.
HTTP
FTP
Upload
FTP
Download
TCP congestion
avoidance.
It correlates with the
throughput drop.
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ppp-server
IP Layer (1)
IP throughput time series
For both downlink and uplink, and at both server and client.
HTTPFTP
Upload
FTP
Download
commview-client
HTTPFTP
Upload
FTP
Download
Throughput drop
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IP Layer (2)
IP packet latency
End-to-end packet latency in downlink and uplink
HTTPFTP
Upload
FTP
Download
Downlink Latency Uplink Latency
Ping
HTTP
FTP
Upload
FTP
Download
Ping
Latency spikes
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RLP Layer (1)
RLP layer throughput time series
Both downlink and uplink
Shows New data throughput, Duplicate data throughput, Retransmit data throughput, and Total throughput respectively.
HTTPFTP
Upload
FTP
Download
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RLP Layer (2)
RLP events:
RLP hole (Nak): both downlink and uplink
RLP Nak Timeouts: downlink at AT
RLP reset: AT and AN requested
RLP Nak Timeout (or
Abort) indicates a RLP hole
at AT cannot be filled when
timer expires.
It correlates with the PPP
FCS error & throughput
drop.
Downlink OTA losses are
usually in multiples of 122
bytes, and rarely exceed
couple of thousand bytes.
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Physical Layer (1)
RF condition
SINR (C/I)
DRC request
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Troubleshooting Example (1)
EVDO field issue: Low throughput
Findings from 3GDQoS tool:
Many TCP timeouts & out-of-sequence due to pkt loss,
which invokes TCP congestion control & window shrink.
Most of the loss occurs outside RAN
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Troubleshooting Example (2)
EVDO field issue: High latency
Findings from 3GDQoS tool:
High latency contributed by wireline network
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Troubleshooting Example (3)
EVDO field issue: Low throughput
Findings from 3GDQoS tool:
Significant RLP loss inside RAN
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Access Terminal (AT)
Test with known / well characterized terminals
Recommend the use of terminals with dual diversity receive antennas
Most PCMCIA based 1xEVDO based terminals offer diversity reception (unlike handhelds)
Beware of desensitization issues
Interference from clock sources within the laptop
Near field effects of antenna spaced close to the PCMCIA card - could hurt signal stability
Use 1xEVDO-only mode during RF optimization
Allows full focus on the 1xEVDO system
Could follow up with Hybrid mode drive for performance benchmarking
Locate and optimize areas for 1xEV to 3G1x handoffs
Chipset types
5500
6500
6800
6850 (MC-EVM)
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Client Settings
64K TCP window, VJ off, PPP data compression on;
W/4 simultaneous TCP connections, the web browsing throughput for MIP/Hybrid mode still provides tremendous gain in throughput.
Web Browsing Throughput
(MIP/Hybrid IE w/4 cnx)
0
100
200
300
400
500
600
700
Clean RF Condition
Web
Bro
wsi
ng IP
-Lay
er T
hrou
ghpu
t (kb
ps)
VJ_off PPP_on 64K
VJ_on PPP_on 64K
VJ_off PPP_off 64K
VJ_off PPP_on 32K
VJ_off PPP_on 32K
VJ_off PPP_off 32K
VJ_off PPP_on 16K
VJ_off PPP_on 16K
VJ_off PPP_off 16K
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Miscellaneous Failures category
Description Several other failures not discussed earlier can occur during call setup
stage or during call Potential causes Call Processing states not in sync between the AP and TP
Cannot sent messages
Timeouts
Other internal errors
Allocate traffic channel failure
TP selection algorithm fails
TP at max dormant session limit
Symptoms / Identification Techniques Show up in one or more of the following depending on the stage the
anomaly encountered AT-initiated Connection Attempt Failures – other failures
Connection released – other reasons
Soft and Softer handoff Failures – Other Reasons
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Miscellaneous Failures (Cont.)
Mitigation Strategies
Often may require custom traces and development support to debug further
Continue to update guidelines based on experience
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Lesson Summary
At the conclusion of this lesson, you should be able to
Perform basic troubleshooting of RF problems (such as lack of coverage, excessive pilots, interference, and non-optimized neighbor lists)
Examine inter-RNC border issues and RNC grouping
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CL3724: End of Lesson
Do not delete this graphic elements in here:
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EV-DO Multi-Carrier Optimization5
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Lesson Objectives
Describe multi-carrier optimization
Analyze inter-frequency handoffs
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Multi-Carrier Scenarios
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Multi-Carrier Optimization Objectives
Minimize call drops and RF access failures in the core area
Provide desired coverage/capacity in the Fn core area
Ensure reliable Fn to {Fi} handoffs as the user approaches the inter-frequency handoff boundary
Minimize RF access failures near the {Fi}/Fn border
Provide reliable inter-frequency handoffs for EV-DO calls originated on Fn in areas external to the expected inter-frequency handoff boundary
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Idle Mode Hashing and Load Balancing
For Border sectors:
Ndiff = (MaximumnumberofUsersSupportedforRevA)*(hdrSNSpare6/100)
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EIS - Enhanced Hashing Support
Allow different hashing classes to be defined for different channels(carriers)
AT is given a class mask to match against the class of a channel (DOcarrier) in the Sector Parameter message
•Class mask is a configuration attribute of the Enhanced Idle StateProtocol
With enhanced hashing, Rev A and Rev 0 carriers in a mixRev0/RevA multi-carrier cell can be put in different hashing classes
•Rev A mobiles hash only to Rev A carriers or to both Rev A and Rev 0 carriers–Controlled via translation parameter
•Rev 0 mobiles hash only to Rev 0 carriers or to both Rev 0 and Rev A carriers–Controlled by the operator
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EIS - Mobile Hashing Algorithm
Supports hashing across carriers based on AT’s technology capability
•Useful only in case of mix Rev A / Rev 0 carrier•Helps segregate Rev A mobiles on Rev A carrier and Rev 0 mobiles on Rev 0 carrier
– Uses Channel List and Extended Channel List information in the Sector Parameters Message (SPM)
– Similar to CDMA Channel List and Extended CDMA Channel List Messages in CDMA 3G1x
– Applies only to Rev A capable mobiles that support EISRev A mobiles without EIS capability will hash to Rev 0 carrier
– Current commercial Rev A mobiles support EIS
•Rev A mobiles hash to a Rev A carrier following Session Setup– Rev 0 channel is listed in Channel List whereas Rev A channel is listed inExtended Channel List in SPM– All mobiles hash to Rev 0 carrier prior to Session Setup– Rev A channel in the Extended Channel List is visible only following EISnegotiation– May impact Access/Control Channel occupancy on Rev 0 carrier
•Hashing based on EIS is not used in case of single carrier, multiple Rev 0 carriers and multiple Rev A carriers
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Translation Parameters – Recommended Values
Enhanced Idle State Protocol Enabled (Service Node-Enhanced Idle State Protocol)
This parameter is used to enable/disable the EIS feature
The recommended setting is Yes
Rev A AT Hash to Rev 0 Carrier Allowed (Service Node-Enhanced Idle State Protocol)
This parameter is used to control Rev A mobiles hashing to Rev 0 carriers.
The recommended setting is Yes, i.e. Rev A mobiles are allowed to hash to both Rev A and Rev 0 carriers.
Rev 0 AT Hash to Rev A Carrier Allowed (Service Node-Enhanced Idle State Protocol)
This parameter is used to control Rev 0 mobiles hashing to Rev A carriers.
The recommended setting is Yes, i.e. Rev 0 mobiles are allowed to hash to bothRev 0 and Rev A carriers
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Basic Call Processing Scenario for IFHO
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Mobile Assisted and AN Directed IFHO Algorithms
IFHO
Enabled legs
in active set?
Different channels
reported in RUM?
Is strongest
diff Chan Pilot
>Strongest same
channel pilot-1
diff Chan Pilot
> same channel
pilot+2
IFHO-enabled
Active legs
> all other Active
legs
IFHO-enabled
active legs
<Directed IFHO
threshold
Perform IFHO
Soft handoff
yes no
yes
yesyes
yes yes
no
no
no
no
no
Mobile
assisted
IFHO
Directed
IFHO
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Off-Frequency-Search Algorithm
Off-Frequency-Search algorithm is strictly AT’s implementation and AN has no control over it
AT performs OFS when the serving pilot strength falls below –5 dB
To minimize impact on the data throughput performance in connected state
To minimize impact on battery life in idle state
AT performs OFS during scheduled 3G1x tuneaway
AT tunes to target frequency after returning from 3G1x
Once every 5.12s if the above pilot strength conditions are met
OFS is supported in the following states/modes:
Connected State MSM6500 (Hybrid mode)
Idle State MSM5500/6500 (EVDO only and Hybrid mode)
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Mobile Assisted and AN Directed IFHO Algorithms
If AT reports Pilots from different channel, AN Directed IFHO is not triggered even if the AN Directed IFHO threshold is met
Implies cannot disable MAIFHO if AT reports different channel pilot information
If PilotAddThreshold for different channel is set to a very high value, AT may not report different channel pilot information effectively disabling MAIFHO
In general, need to set both AN Directed and MAIFHO thresholds
Mobile uses PilotAddThreshold and PilotDropThreshold for Different Channels (translation parameters) to report pilots from target carrier following OFS
Latest recommendations:
Threshold for AN Directed IFHO: -5 dB
Thresholds for Mobile Assisted IFHO: 1: 3dB, 2: 1.5dB
Need to fine tune these threshold values depending on RF/Terrain conditions as well as scenarios (Wedding Cake versus Disjoint), etc.
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How to Enable Inter-Frequency Handoffs
Define the different carrier neighbors in the Neighbor Sector forms
Set (up to 6) AN Directed IFHO Target neighbors in the Neighbor Sector form
Create/populate IFHO Targets for a sector-carrier
Set IFHO Enabled to yes in the Sector-Carrier form
Set IFHO Thresholds in the Sector-Carrier form
For MAIFHO
Strongest DiffChan/SameChan PilotPN Differential for IFHO
Combined DiffChan/SameChan Signal Differential for IFHO
For AN Directed IFHO
PilotPN Signal Strength Threshold for IFHO
Set Maximum Different Channel Entries in Neighbor List Sent to AT to a non-zero value
Increase Maximum Entries in Neighbor List Sent to AT by the number of Diff. Channel neighbors to avoid possible truncation in the number of same channel neighbors. Max. Entries in NL can go up to 31.
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Inter-Frequency Handoff Translation Parameters
Flag to Enable IFHO (Sector carriers –general)
Inter Frequency handoff Enabled
Thresholds for Mobile Assisted IFHO (Sector carriers –general)
Strongest DiffChan/SameChan PilotPN Differential for IFHO (1)
Combined DiffChan/SameChan Signal Differential for IFHO (2)
Threshold for Directed IFHO (Sector carriers –general)
Pilot PN Signal Strength Threshold for IFHO
Configurations for Directed IFHO
Directed Inter Frequency Handoff (IFHO) Target (Neighbor Sectors)
Inter Frequency Handoff (IFHO) Target Band Class (IFHO Target)
Inter Frequency Handoff Target Channel Number (IFHO Target)
Others
Maximum Entries in Neighbor List sent to AT (Sector carriers –general)
Maximum Different Channel Entries in Neighbor List Sent to AT (Sector carriers –general)
Reset Report Time Interval for IFHO for RUMS (Service Node –general section 1)
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Neighbor List for IFHO
Access network maintains two sets of neighbor lists: Same Channel and Different Channel neighbor lists
Different Channel neighbors are identified by setting “ChannelIncluded” field to 1 in both SectorParameters and NeighborList messages
Maximum size of the combined neighbor list is defined by the translation Maximum Entries in Neighbor List sent to AT
Maximum size of different channel neighbors is limited by the translation Maximum Different Channel Entries in Neighbor List sent to AT
Maximum number of entries for same channel neighbors is determined by (Maximum Entries in Neighbor List sent to AT - Maximum Different Channel Entries in Neighbor List sent to AT)
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Provisioning of Neighbor List
Key IFHO neighbors must be provisioned at the top of the neighbor list (NeighborID <=12)
By default, the first 12 NeighborIDs occupy the 12 IFHO neighbor list entries (Max. Different Channel Entries in Neighbor List sent to AT = 12)
Common Carrier / Wedding Cake scenario
Directed IFHO neighbors have the highest priority among different channel neighbors regardless of the NeighborIDs
Will make it to the Directed IFHO neighbor list (up to 6)
If more than 6 neighbors are marked as Directed IFHO neighbors, first 6 neighbors with the lowest NeighborIDs will make it to the Directed IFHO neighbor list
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Combined Neighbor List sent to AT
MSM5500/6500 mobiles support only one frequency per each neighbor Pilot PN
Becomes an issue when a Pilot PN is a neighbor on both same and different channels
If such a Pilot PN is marked only as different channel neighbor, AT will not search/report this PN for soft/softer handoff. May lead to a drop call
Access network workaround
Different channel neighbors that are also same channel neighbors, will not be included in the combined neighbor list
Logic is that such neighbors are most likely to be added in the active set as soft/softer handoffs on the same channel before they become strong enough to have impact on mobile assisted IFHO
Once in the active set, these Pilot PNs can be included in the neighbor list as different channel neighbors
MSM6800 (Rev A) mobiles support multiple frequency per each neighbor Pilot PN
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Border Sector/Carrier -- IFHO Wedding Cake Example
F1/F2 region
Cell A Cell B
F1 region
Border Sector/Carrier
F2 is the carrier that would be marked as a
border sector/carrier; if customers decided to
do it. Border enable will modify the load
balancing algorithm and the Sector
Parameters Message.
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Sector Carrier and Target Forms – 567_1
Optional ?
Check NL ?
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Neighbor Sector Form – 567_1 (id=1)
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Neighbor Sector Form – 567_1 (id=2)
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Sector Carrier and Target Forms – 567_3
Optional
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Neighbor Sector Form – 567_3 (id=1)
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Neighbor Sector Form – 567_3 (id=2)
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Border Sector/Carrier ---- IFHO Disjoint Carrier Example
F2 region
Cell A
Cell B
F1 region
Border Sector/Carrier
F2 is the carrier that would be marked as a
border sector/carrier; if customers decided to
do it. Border enable will modify the load
balancing algorithm and the Sector
Parameters Message.
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Sector Carrier and Target Forms – 234_1
Check NL ?
Optional ?
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Neighbor Sector Form – 234_1
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Sector Carrier and Target Forms – 319_2
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Neighbor Sector Form – 319_2
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Adding Carrier Recommendations - 1
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Adding Carrier Recommendations - 2
On 200_gamma (F2) ?
Cell 100Cell 200
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Adding Carrier Recommendations - 3
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Dropping Calls on Borders ?
F1/F2 region
Cell A Cell B
F1 region
Did you drop on F2 or F1 ?Why ?
Potential solutions ?
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Translation Application Note # 4
Please refer to TAN # 4 for recommended settings and more information.
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Intergeneration Handoffs – Personality Switch
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Session/Connection Setup
UATI Assignment
Connection
Establishment for
Session Configuration
Session Configuration
Connection
Establishment with
new parameters
AT AN
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Session Configuration Protocol (SCP)
SCP is in the session layer and is used to negotiate all application, protocols and related attributes that will be used during the entire session
After negotiation the connection is dropped and re-established for the setting to take place
Any change to the negotiated parameters requires re-running of SCP, dropping and re-establishing the connection
SCP always takes place on the traffic channel
SCP supports two phases of negotiation
AT initiated negotiation
Used to negotiate protocols
AN initiated negotiation
Used to override default value of the attribute
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SCP for Rev. 0
Performed for every new session and whenever a subtype need to be changed
SCP is costly and connection has to be released & re-established for new setting to take effect
How to establish a Rev. A session?
How to handle Rev. A and Rev.0 session across coverage boundaries?
How to avoid renegotiating the entire session to change a single attribute?
Connection Establishment
ConfigurationRequest
ConfigurationResponse
ConfigurationRequest
ConfigurationResponse
ConfigurationRequest
ConfigurationResponse
ConfigurationRequest
ConfigurationResponse
ConfigurationComplete
ConfigurationComplete
(SessionConfigurationToken)
ReleaseConnection
AT AN
AT-in
itia
ted
AN
-initia
ted
ConfigurationStart
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Rev A Session/Personality
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Multiple Personalities
A personality is a complete set of negotiated protocol subtypes,
application subtypes, attributes values and public data
Indexed by the four most significant bits of the
SessionConfigurationToken (SCT)
Each AT can support up to “PersonalityCount” (attribute) personalities
Personality with “0” index in defined as the main personality, which is
used together with “HardLink” subtype to avoid negotiating identical
attributes across multiple personalities
Only one personality is in use at a time
AT includes the current SCT (personality in use) in the access channel
MAC header (this is how the AN figures out the personality in use)
Default Packet Rel. 0 and Default Packet Rev. A personalities are
introduced in R27. R28 and later have MFPA and EMFPA, these will be
covered in the QoS section
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Generic Attribute Update Protocol
Need an alternative light weight protocol for changing attributes
It is not always desirable to run SCP, since the connection has to be released and re-established for the changes to take effect
GAUP is used to change parameter values of certain attributes
The standard clearly defines these attributes
Protocol and application subtypes cannot be individually GAUPed
Protocol and application subtypes can be GAUPed via personality switch
Connection release is not required except when GAUPing personality
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Generic Attribute Update Protocol
GAUP uses generic message to change values of GAUPable attributes
Attribute Update Request (send by initiator AN or AT)
Attribute Update Accept (send by receiver AN or AT)
Attribute Update Reject (send only by the AN)
GAUP messaging can sent over access channel, control channel or traffic channel
GAUP can be sent any time during a connection or a session
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Personality Switching
Rather than use SCP whether the AT cross a coverage boundary, negotiate multiple personality and switch personality as needed at the coverage boundary
How is the personality switched?
The SCT is a GAUPable attribute
The AN sends an “AttributeUpdateRequest” (AUR) with new SCT in the attribute field
Personality switch strategy
No connection, Personality Switch
“Rev. A to Rev 0” or “Rev.0 to Rev. A”
Connection is open, Personality Switch Handoff
downgrade only “Rev. A to Rev. 0”
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Idle Personality Switch
Note: Personality switch for an idle AT only occurs when it accesses the network. If an idle AT moves across Rev A and Rev 0 cells without accessing the network, the personality switch is not performed.
RouteUpdate/ConnectionRequest
Rev 0 Sector Rev A AT
Idle, Rev ASCT = 0001
(Using Access Channel with SCT =0001 in header)
ACAck
AttributeUpdateRequestTrafficChannelAssignment
(SCT=0000)/
Using Control Channel)
Pilot + DRC
RTC Ack
AttributeUpdateAccept
TrafficChannelComplete
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RouteUpdate (Rev A and Rev 0 pilots)
Rev 0 Sector in Rev A RAN
Rev A AT
Active Rev ASCT = 0001
AttributeUpdateAccepted
TrafficChannelComplete
AttributeUpdateRequest (SCT=0000)
ConnectionClose/TrafficChannelAssignment
ConnectionClose
Pilot + DRC
RTC Ack
Determined if hand-down is needed
In the near future idle personality switch from A to 0 will also be triggered based on the pilot
strength evaluation and the Personality Switch Threshold, similar to the active personality switch
from A to 0.
Active Personality Switch from Rev A to Rev 0
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Personality Switch Trigger (w/Connection)
RouteUpdateMessage
Any
Candidate
Rev. 0 only?
RNC creates two lists:
• Rev. A list: Active Set members with
Keep=1, ranked by decreasing strength
• Rev. 0 list: Candidate that support Rev. 0
only, ranked by decreasing strength
Combined Rev. A
Strength>=Combined Rev. 0
only + PresonalitySwitchThreshold
?
Follow regular
process
Perform Personality Switch.
Handoff to strongest six among
(Active Keep=1, candidates)
Ignore Rev.0 only
candidates
No
Yes
Yes
No
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Rev. A Mobile Assisted IFHO
• Consider only Active set members with keep=1 and Rev-A-enabled Candidates that are on the Combined Neighbor List
• Create one list for each frequency represented in the RUM:
- One list for current frequency
- One list for each different frequency
Is strongest Rev-A-enabled same-channel pilot at
>= different channel pilot+1?
YES
Select different-frequency list with greatest combined signal strength
NO
Combined SS of strongest
different-channel list >= Combined
SS of current frequency +2?
Handoff to different-frequency using strongest up-to six candidates of the list
YES
NOCombined SS of revised different-frequency list >= current frequency
list +2?
• Perform Personality Switch to Rev-0 on Active Set
•Handoff to different-frequency using strongest up-to six candidates of the list
YES
NO
Add back Rev-0-only
pilots into the
strongest different-
channel list
Perform soft/softer evaluation
• Precedence is given to
Rev. A to Rev. A IFHO
• If such a handoff is not
possible then consider Rev.
A to Rev. 0
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Rev. A Mobile Assisted IFHO [Cont.]
Mobile Assisted IFHO is evaluated if the PilotPN strength measurements formdifferent frequencies (FIHO candidate channels) are reported in the RouteUpdatemessage.A Mobile Assisted IFHO is triggered if: The strongest different channel (IFHO candidate channel) pilot strength (Strngt
DiffChan) is larger than the strongest same channel pilot strength (Strngt SameChan) minus a Strongest DiffChan/SameChan Pilot PN Differential for Mobile Assisted IFHO (dB) threshold represented as delta 1. The Strongest DiffChan/SameChan Pilot PN Differential for Mobile Assisted IFHO (dB) threshold is a translation parameter entered on the Sector Carrier – General EMS Gui page and ranges between 1 and 7 dB in 0.5 dB increments with a 5-dB default.
The combined (all) Rev A different channel pilot strength (Cmbnd Rev A DiffChan) is equal to or larger than the combined same channel pilot strength (Cmbnd SameChan) by the Combined DiffChan/SameChan Signal StrengthDifferential for Mobile Assisted IFHO (db) threshold represented as delta 2. This threshold is also a translation parameter entered on the Sector Carrier – General EMS Gui page and ranges between 1 and 7 dB in 0.5 dB increments with a 5-dB default.
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Rev. A Mobile Assisted IFHO [Cont.]
The first condition test determines if an IFHO should be performed by
determining if the PilotPN of the strongest IFHO candidate is greater than the
PilotPN of the strongest virtual handoff candidate’s PilotPN minus a differential
(delta 1). If the first condition is not met, a virtual soft handoff is perform on the
same channel.
If the condition is met, the second condition is tested to determine if the IFHO handoff can be made to a Rev A carrier, maintaining the Rev A connection. If the combined PilotPN signal strengths of all Rev A IFHO candidates is equal to, or greater than the combined PilotPN strengths of all virtual handoff candidates plus the delta 2 differential, Rev A IFHO is triggered.
If the second test criteria is not met, Rev 0 IFHO personality switch candidacy is determined by comparing the PilotPN strengths of the combined Rev 0 and Rev A IFHO candidate (different) channels with combined PilotPN strengths of all virtual handoff candidates plus the delta 2 differential. If the former is equal to or greater than the latter, a Rev 0 personality switch and IFHO is executed; otherwise a virtual soft handoff is performed.
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Lesson Summary
At the conclusion of this lesson, you should be able to
Describe multi-carrier optimization
Analyze inter-frequency handoffs
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CL3724: End of Lesson
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• Multiple Flows will impact the Call Capacity in OHM and TP and BTS. Multiple Flows is built on top of Rev-A. Every flow can be viewed as a connection. So if a Connection typically has 2 flows expect the capacity to be reduced by 50% in terms of the number of calls in the Traffic Processor. Voice and Video Flows involve smaller packets causing more impacts to Traffic Processor.
• OHM is involved in QoS setup for every flow and also for Admission Control decisions when a flow is activated. More messages are being sent between TP, OHM and BTS to support multiple Flows causing significant performance impacts to OHM.
QoS - Capacity and Performance
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Handoff Matrix Summary reports
Do not delete this graphic elements in here:
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EVDO Hardware and Other Impacts9
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Lesson Objectives
Identify the hardware upgrades needed for Rev A and other EVDO RF functionalities
Identify the components of the Universal Network Cabinet (UNC)
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Modem Upgrade (CSM6800)
The SB-EVM/SB-EVMm:
uses Qualcomm ASIC Tile based on CSM6800 chipset (rev. A and rev. 0)
provides higher capacity in terms of number of channels supported: supports 192 CEs in RL for 96 users (2-Way diversity) and 288 flows in the forward link. Full capacity of 192 users and 576 flows. In Rev A a flow is termed as an open reservation in which a stream of data between the AT and a specific web location.
has an optional tile that could add additional 192 CEs for greater capacity or the same capacity with 4-Way diversity.
provides Pilot Interference Cancellation
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What is the RL PIC in EVDO?
In the RL of EVDO, The pilot signal is important for RL power control and channel estimation/demodulation of AT, but is interference for other ATs.
For the VoIP where a large number of ATs transmit at low data rates (9.6kbps, 256 bit), a significant percentage of AN received power is from pilot signals transmitted by the ATs.
By removing this pilot interference, the EVDO RL can support more VoIP users.
Qcom is offering PIC as an optional FPGA feature supported by the CSM6800 solution
For the 3GPP2 channel mix, about 60-70% of the overall pilot power can be cancelled from users in the sector
Pilot
30%
DRC/DSC/
ACK/RRI
Data
40%
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PIC Preliminary Improvement
For the 3GPP2 fading channel mix, about 70% of the overall pilot interference from in-sector ATs can be cancelled by PIC in the EVDO Rev link.
Simulation indicates the VoIP capacity improvement
PIC could provide about 15% more VoIP users in EVDO, or giving the users about 27% more data power at the same data rate.
With PIC=70%, the voice capacity becomes about 41 Erlangs (52 users/sector).
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Rev. A Four Way Diversity
From 2Rx to 4Rx antennas at AN, the long-term pilot Ecp/Nt requires about 2.3 dB less with TG = 4 subpkts.
Taking into account all channels, the average Ec/Nt per antenna for 256 payload provide about 40% improvement, which can be used to estimate the performance improvement of full-buffer throughput.
Link Budget (or Cell Coverage)
The gain of Tx power at AT is about 2.4 dB. For the data rate, the coverage could be doubled as long as a similar performance (1% RPER) is kept.
Reference:
J. Salz and J. Winters, “Effect of Fading Correlation on Adaptive Arrays in Digital Mobile Radio”, IEEE Trans. On Veh. Tech., Vol. Vt-43(4), pp 1049-1057, Nov. 1994.
M. Fan and E. Esteves, “The Impact of Antenna-Array Receiver on the Reverse Link Performance of CDMA2000 1xEV High Rate Packet Data Systems”, IEEE VTC2003, Fall Orlando, FL.
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Rev. A Capable ATs (MSM6800)
Equalizer (better DRC distribution due to better SINR)
Helps to reduce multi-path (ISI) interference
• Helps achieving higher data rates such as 3.1 Mbps
Helps to suppress interference from other sectors and other carriers
Different Operation Modes in Hybrid (less interruption when checking on 3G-1x)
•“Rev. A capable access terminals may provide performance benefits in Rev. 0 operation over previous generation of handsets. Two contributing factors are Simultaneous Mode operation and channel equalization on the forward link.”
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SINR Improvement
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2GB Memory AP-CPU Upgrade
CP2140
Increases the number of UATI Sessions to 65K(R27)/100k(R28) per AP
1GB Cards maximum number of session per RNC frame 320K
2GB Cards maximum number of session per RNC frame 800K(R28)
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Two or more functions combined
Bearer function
Control function
OA&M function
DACS
IP Backhaul
Network
Packet
Data
Network
Ethernet
Switch
MCC/
TLWS
Router
PDSN
9270
1xRNC
Frame Relay
Backhaul
Network
9281
PS
DACS
Ethernet
Backhaul
Network
Ethernet
Switch
9271 EV-DO
RNC
1xEV-DO
Backhaul
Network
PSTN
DACS Router
3G1X CDMA
Base Station
Mixed-mode
Base Station
3G1X CDMA
Base Station
1xEV-DO
Base Station
Access
Terminal
Access
Terminal
Access
Terminal
Access
Manager
(9290
MM/MMC)
9256 OMP
9253
OMC-RAN
OA&M
Network
CDMA/EV-DO Network with new product names
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OMP-FX and OMC-RAN
OMP-FX
SUA
Emergency Access
Data Repository
ROP
Tools and Scripts
ECP Direct Connection
SM Collection/Dist.
TICLI
SDP
RC/V
Cut-thru to FPS(5E)
TICLI
RC/V GUI
FPS Management
Super Overview
Integrated Fault Management
North Bound Interface
OMC-RAN
System CLI
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AP
AP
To External Network(PDSN/AAA)
To OA&M Network(OMP-FX/OMC-RAN/MSC)
GigEFiber
100 Base T (to OAM Network)
100 Base T (to OAM Network)
Layer 2Switch A
Layer 2 Switch B
CajunSwitch
B
CajunSwitch
A
TP
TP
TP
TP
GigEFiber
GigEFiber
STPGigEFiber
VRRP
RAN Data VLAN
Inter-Router VLAN
Inter-Router VLAN
Hand-off Network VLAN
GigE/FE
GigE/FE
IPBH for EV-DO
Most of the QoS features on MLPPP.
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1x T1/E1 # n
DO T1/E1 # n
1x T1/E1 #1
T3/OC-3/OC-12
E3/STM-1/STM-3
AggregationRouter B
DO RNC
RNCs
MSC
FMM APs
PSUs
RNCs
T1/E1
Mux
CELL
SITEs
1xEV-DO
&
3G1x
Aggregation Router A
MLS A
MLS B
VRRP STPDO T1/E1 #1
EBH for EV-DO
OAM
Ethernet
Access
Transpor
t
Network
100 Base-FX
UNI1_cell
UNIn_cell
UNI_nw_standby
UNI_nw_active
Multiple cell
sites
Multiple cell
sites
CELL
SITEs
1xEV-DO
&
3G1x
Shared Aggregation Router and MLS pairs
Converged Backhaul Network
1000
Base-SX
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Universal Network Cabinet (UNC)-Based 1xEV-DO RNC
Doubles the capacity of current R1SR RNC frame
Two independent Universal Shelves, each housing four independent FMS-410S (SUN Netra CT410 server) drawers
Two independent Extreme X450a-48t Ethernet MLS switches (cabinet switches), providing redundant LAN networks within cabinet
Cabinet switches provide the following feature over the R1SR RNC frame Cajun switch:
• L3 capability
• IPV6
• Increased security
• Gigabit port speed
• Larger number of fiber ports
• Greater fiber bandwidth
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Cross Technology Capabilities
3G-1x Circuit Services Notification Application (a.k.a., Cross-Paging)
Objectives:
Permit MS/AT to Monitor cdma2000 (Only) to Save Battery Life While Still Operating Correctly for Packet Data Service via HRPD
Permit an MS/AT that is Monitoring HRPD for Packet Data to Receive Important cdma2000 Events (E.g., Page, SMS, Crossing of cdma2000 Paging Zone Boundary, etc.)
Multimode Capability Discovery Application Discover the Specific Capabilities of Multi-mode Devices, e.g., the Ability to Support Hybrid MS/AT
Operation
Discover the Limitation of the AT’s Multimode Operating Capabilities (e.g., Can or Cannot Simultaneously Monitor Common Channels of HRPD and cdma2000)
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Cross-Notification Examples
Delivery of Unicast SMS to the MS/AT over the
HRPD Air Interface
HRPD BS MSC
a
b
time
HRPD: 3G1XServices packet
(data burst message)
c
MS/AT
ADDS Page Ack
ADDS Page
T3113
d
HRPD: SLP ack)
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Cross-Notification Examples
Delivery of a Page to the MS/AT over the HRPD
Air Interface
cdma2000
BSMSCMS/AT
a
b
time
d
c
e
HRPD BS
1x: Page Response Message
Paging Request (conditional)
T3113
Paging Request
HRPD: 3G1XServices packet
(General Page Message)
Complete L3 Info: Paging Response
T3113
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Delivery of High
Rate Packet Data
Service Option
Page
cdma2000
BSMSC PDSN
MS/
AT
c
time
b
d
e
fT
3113
g
T3210
i
a
j
k
HRPD BS
n
m
l
o
h
Data flow
Connection establishment
HRPD: 3G1xServices packet (Registration)
HRPD: 3G1xServices packet (Registration Request Order)
Location Updating Accept
Location Updating Request
Paging Request
1x: page with SO 59
1x: Page Response
Complete L3: Info Paging
Response
T311
BS Service Response
BS Service Request
1x: Release Order
and L2 Ack
HRPD: 3G1xServices packet (Registration Accepted Order)
Data flow
MaxIdleTunnelTime
1x: Registration
Location Updating Request
Location Updating Accept
1x: Registration
Accepted Order
p
q
r
s
packet data
T3210
Cross-Notification Examples
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Hybrid Mode
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Simultaneous Mode
•Mid Cell FTP Throughput
Simultaneous: 1398 Kbps
Hybrid: 1087 Kbps
Both Rev. 0
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HPT
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Forward Link Handoff with DSC
In Rev 0, service may
be interrupted during
handoff to BTS2.
In Rev A, BTS2 is
notified of an
impending handoff by a
DSC value, which is
transmitted DSClength
slots before the DRC
Cover change.
The value of DSClength
is specified by the
Enhanced Forward
Traffic Channel
protocol.
Forward link serving cell
BTS1
Forward link serving cell BTS1
Forward link serving cell BTS2
Forward link serving cell BTS2
DRC Cover change
DRC detection at BTS1 & BTS2
•Transfer to BTS2
BTS1 send DSC change indication (DSCI)BTS2 send Forward Desire Indication (FDI)
BTS1 send Forward Stop Indication (FSI)
DRC Cover change
BTS2 Starts transmission
time
•time
DSC Length
Forward Link Handoff in Rev A
Forward Link Handoff in Rev 0
Service interruption
DRC Cover change
•Transfer to BTS2
SCC detection at BTS1 & BTS2
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Forward Link Handoff with DSC
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Data over Signaling (DoS) Protocol
Typically, the user data traffic is processed by the RLP protocol.
DoS provides an alternate path for the data.
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Core Transport Network
When IP routing occurs between multiple sites, an edge router or gateway is required at each site to enable communication outside the local subnet
Network IP Routers
MPLS (Multi Protocol Label Switching) and Diffserv support to provide timely
delivery of VoIP packet frames through one or more managed IP networks.
The diffserv code points must be chosen appropriately and an appropriate per-hop behavior must be specified in each router.
PDSN :The hardware and software architecture impact to the PDSN is vendor dependent.
Expected to comply with TIA-856-A-1, TIA 1054, IS835D and TIA-878-A
Standards
Comply with Enhanced Multi Flow Procedures in TIA-878-A for establishment and release of auxiliary A10 connections both concurrent and asynchronous with establishment and release of the main A10 connection.
Support A10, IP Flow Based, Accounting.
Support Flow Mapping and Treatments for HRPD Non-Specific Traffic Flow Templates via the Resv/ResvConf message procedures defined in TIA-835-D.
Support ROHC in conjunction with SO 67 and Alcatel-Lucent DSCP marking and processing assumptions
Support the Ty interface to the PDF and shall perform Bearer Control Point/PEF function as defined in 3GPP2 MDD SBBC standard X.S0013-012-0 v1.0.
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35 VoIP Erlang – Simulations
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
10 30 50 70
Delay Bound (ms)
Sati
sfi
ed
User
Perc
en
tag
e
VoIP Only
5 BE Users
10 BE Users
BE users have little impact on VoIP performance.
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Aggregate BE Throughput (RLP) – Simulations
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
0 10 20 30 40
VoIP Erlang
Data
Th
rou
gh
pu
t (k
bp
s)
1
5
10
BE throughput reduction is non-linear, especially when the VoIP loading is low.
VoIP packets take more slots per VoIP call comparing with high loading case.
loss of RF efficiency for the VoIP occupied slots, as BE traffic can only be carried in MUP as “piggy-back” traffic.
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Lesson Summary
At the conclusion of this lesson, you should be able to
Identify the hardware upgrades needed for Rev A and other EVDO RF functionalities
Identify the components of the Universal Network Cabinet (UNC)
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CL3724: End of Lesson
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Course Summary
You are now able to do the following:
Describe 1xEV-DO network from an RF perspective
Identify the major factors in EVDO RF performance and troubleshooting
Describe multi-carrier optimization
Describe QoS
Explain the features and functions of EVDO optimization tools
Analyze EVDO optimization case studies and outline their solutions
Describe EVDO hardware and other Impacts
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Requirements to Obtain Course Credit
To get credit for taking this course do the following:
1. Complete the course
2. Complete the end-of-course assessment or L2A
3. Complete the course evaluation