Summary Architecture

GSM & WCDMA

Mtr. Axel Abraham Valdes Vargas

GSM

OSS

DESIGN

AIR

INTERFACE

GSM

The HLR is a centralized network database that stores and manages all mobile subscriptions belonging to a specific operator. It acts as a

permanent store for a persons subscription information until that subscription is canceled. The information stored includes:

Subscriber identity Subscriber supplementary services Subscriber location information Subscriber authentication information

Visitor Location Register (VLR)

Home Location Register (HLR)

When a subscriber roams into a new MSC service area, the VLR connected to that MSC requests information about the subscriber from the

subscribers HLR. The HLR sends a copy of the information to the VLR and updates its own location information. When the subscriber makes a call, the VLR will already have the information required for call set-up.

The VLR database contains information about all the mobile subscribers currently located in an MSC service area. Thus, there is one VLR for

each MSC in a network. The VLR temporarily stores subscription information so that the MSC can service all the subscribers currently visiting

that MSC service area. The VLR can be regarded as a distributed HLR as it holds a copy of the HLR information stored about the subscriber.

AUthentication Center (AUC)

The main function of the AUC is to authenticate the subscribers attempting to use a network. In this way, it is used to protect network operators

against fraud. The AUC is a database connected to the HLR which provides it with the authentication parameters and ciphering keys used to

ensure network security.

Equipment Identity Register (EIR)

The EIR is a database containing mobile equipment identity information which helps to block calls from stolen, unauthorized, or defective MSs. It

should be noted that due to subscriber-equipment separation in GSM, the barring of MS equipment does not result in automatic barring of a

subscriber.

The Base Station System (BSS) is responsable for all the radiorelated

functions in the system

1. BSC (low capacity)

2. TRC the rate used over the air interface

and that used by MSC/VLRs are different -

33.8 Kbps and 64 Kbps respectively

3. RBS (ericsson 2000 series)

4. BSC/TRC can be handled 15 remotes

BSCs (high capacity)

RADIO

Mode Term Description

Registration This is the process in which an MS

informs a network that it is attached.

Roaming When an MS moves around a network in

idle mode, it is referred to as roaming.

International

Roaming

When an MS moves into a network which

is not its home network, it is referred to as

international roaming. MSs can only roam

into networks with which the home

network has a roaming agreement.

Location

Updating

An MS roaming around the network must

inform the network when it enters a new

LA. This is called location updating.

Paging This is the process whereby a network

attempts to contact a particular MS. This

is achieved by broadcasting a paging

message containing the identity of that

MS.

Active Handover This is the process in which control of a

call is passed from one cell to another

while the MS moves between cells.

Idle

Transmission Problems

Path loss

shadowing

multipath fading

Rayleight fading

time dispersion

time alignment

Solution Problems

Interleaving

antenna diversity

space diversity

polarization diversity

adaptative equalization

frequency hopping

timing advance

use 63 bittimes (35 Km), with extended

range (70 Km) or (121 Km) using 2 TS

Rate (Kbps)

Full rate 13

Half rate 6.5

Enhanced full rate (EFR)13

Logical Channel

Control Channel

Traffic Channel

BCCH FCCH, SCH, BCCH

CCCH PCH, AGCH, RACH

DCCH SDCCH, SACCH, FACCH

Full rate and EFR

Half Rate

CHANNELS

Burst types

Normal

Frequency correction

Synchronization

Access

Dummy

26 TDMA frame multiframe: used to carry

TCH, SACCH and FACCH

51 TDMA frame multiframe: used to carry

BCCH, CCCH, SDCCH and SACCH

Signal strength

Signal quality

Time alignment

Locating

FEATURES

Load sharing Assignment to another cell HCS Intra cell handover OL/UL Call disconnect

DESIGN

Cell Planning Process 1. Traffic & Coverage analysis

2. Nominal Cell Plan

3. Surveys

4. System design

5. Implementation

6. System tuning

Ericsson recommend between 25 y 33 mE when planning GSM networks

GoS = 2%

4. System design

1. selecting the sites for the radio

equipment

2. selecting the radio equipment

3. configuring the radio equipment

Omni directional = Coverage

Sector cell = Capacity

PROCESS

Adjacent frequencies C/A are the frequencies with a landslide of 200 KHz of the Carrier and

preferably also must be avoided in the same Cell and in their neighbors, so that they cause to

problems of Interference and Quality in the call.

Ericsson recommends that relation C/A in GSM is of -9 dB

Maximum radius of a GSM cell = 35 Km

Whit 2 TMA = 70 Km (large coverage and low capacity)

C/I is greater than 9 dB (ericsson recommend 12 dB)

C/A is greater than -9 dB (ericsson recommend that higher that 3 dBm) F2 = F1 + 200KHz

Plan 7/21 recommend for networks whit higher interference

4/12 4 sectors site and 12 group frequency

CONCEPTS

Frequency hopping = help to reduce the interference for adjacent

frequency

Overlaid and Underlaid subcell. Each overlaid subcell servers a

smaller area than the corresponding underlaid subcell and the

frequency reuse distance for the overlaid subcells can therefore be

made shorter

Base Band hoppping

Synthesizer hopping

The Hierarchycal Cell Structure (HCS) characteristic divides the

Cellular Network in up to 8 layers, the highest layer is used for

Cells with great cover, the layers of down for small cells and the

micros are used to provide capacity in areas with traffic

concentration. The different layers from cells can work by

designation of priority with the low layer but with the highest

priority.

HW

Combining and distribution unit (CDU) The CDU is the interface between the TRUs an

the 2-way antenna system. The task of the

CDU is to combine signals to be transmitted

from various transceivers and to distribute

received signals to the receivers.

CONCEPTS

Frequency hopping

Frequency hopping

OSS

OSS Tools

Cellular Network Administrator CNA

Performance Measurement Recordings PMR

MTR CTR

CER

Radio frequency Optimization RNO MRR

NCS/NOX

FAS/FOX

CNA works under three concepts:

1. VALID AREA

It represents the present cellular network that is to say, provides information of the

parameters of the cells that its in the network. Only there is a VALID AREA that

corresponds to each cellular Network and is used to recover information of Values of the

parameters and as a data base for the new creation of Planned Area.

2. PLANNED AREA

It represents changes planned in the Cellular Network. This area Is used to out of line

realise several changes in the network.

3. FALLBACK AREA

It is one snapshot copie of the Valid Area in a specific time and it reflects an historical

one of the network, can be used like back-up before some update in the network. A new

Planned can be created Area to start off a Fallback Area.

PMR

MTR mobile traffic recording

For one or more associate MSC's as well as its BSCs

Up to 64 IMSIs (to level MSC)

Independent measurements by each IMSI

Maximum duration of 1 week

CTR cell traffic recording

Events (and measurements) in a cell in particular

Only one cell by each BSC in the same time

Maximum duration of 1 hour

RNO

MRR

NCS/NOX Neighbor Optimization

FAS/FOX Frequency Optimization

Funciones de la BSC

MRR (Measurement Result Recording)

mrrfil

BAR (Broad Cast Control Channel Allocation List Recording)

barfil

RIR (Radio Interference Recording)

rirfil

WCDMA

1. APPLICATION LAYER

2. CONTROL LAYER

3. CONNECTIVITY LAYER

APPLICATIONS

SGW, MSC, HLR/HSS, IMS, GMSC

CONNECTIVITY, SGSN, MGw, GGSN, WCDMA Acsses, GSM Accsses, PSTN, ISDN, INTERNET, INTRANET

Red WCDMA

DISEO

INTERFASE

DE

AIRE

OPTIMIZACIN

SERVER

MSC

SGSN

GGSN

RNC BSC/TRC

MGw

BTS Node B

WCDMA GSM

UE

Iub

Iur RNC

Uu

Iu CS

Iu PS

A-bis

Gb

A

BSC A-ter

Um

Gn

Interfaces

Iu interface = The Iu interface connects the UTRAN to the CN and is split in two

parts. The Iucs is the interface between the RNC and the circuit switched domain

of the CN. The Iups interface is the interface between the RNC and the packet

switched domain of the CN.

Uu interface = The Uu interface is the WCDMA radio interface

with in UMTS. It is the interface through which the UE accesses

the fixed part of the network.

Iub interface = The Iub interface connects the Node B and the RNC.

Iur interface = This RNC-RNC interface was initially designed in order to provide

inter RNC soft handover, but more features were added during the development.

BASIC CONCEPTS

Radio Access Bearer = Service offered by a network WCDMA

RAB Configuration (Kbps)

Voz 12.2

64 CS

64/64 PS

64/128 PS

64/384 PS

64 HSDPA, 5 CODES PS

57.6 CS

16/64 PS + INTERACTIVE, 8/8 PS

16/128 PS + INTERACTIVE, 8/8 PS

64/64 PS

64/128 PS

64/384 PS

Conversacin

Streaming

Interactivo

Background

Spreading Factor = it is the process of widening of the signal, with which the bandwidth is

increased bases beyond the bandwidth required by a signal, for himself to

accommodate the information and to pass on to majors speeds

It is important to consider that each Radio Access Bearer

handles Spreading Factor (SF) different depending the type

on watch that it is asked for.

Channel Element = one talks about to the resources required in node B (Hw) to provide

capacity for the services asked for by the users such as voice, data, streaming

etc

SIZING OF NETWORK WCDMA

For the calculation of Chanel Elements used in each node B, the following

accountants take care who indicate the number to us of Links Radio

pmNoOfRadioLinksSf128

pmNoOfRadioLinksSf16

pmNoOfRadioLinksSf256

pmNoOfRadioLinksSf32

pmNoOfRadioLinksSf4

pmNoOfRadioLinksSf64

pmNoOfRadioLinksSf8

In order to obtain the number of CE the

accountant by the number of CE is due to

multiply indicated in the CE stairs

These accountants are classified by Spreading Factor and enter radiolinks that happen

between mobile and Node B in a determined period, in such a way that to obtain Channel

Elements the count is made of Radiolinks and they are related to the stairs of Channel

Elements

Channel Element Stair

Channel Element in: SF # SF #

AMR 12.2 Kbps 64 1 128 1

CS64K 16 4 32 4

PS64K 16 4 32 4

PS128 8 8 16 4

PS384 4 16 8 16

Ul Dl

Input data for the design of a network 3G

1. Equipo preliminar (RAN)

2. Naming Convention (RAN)

3. IP ranges (IP)

4. Netwok topology (Tx)

5. Conectividad (Tx)

6. Traffic Model and services to be offered

7. RF nominal plan

8. RF detailled plan

9. CORE network design: SGSN (PS), MGw (CS), OSS

(O&M)

10. Sincronization

Speech Data

Required bandwidth

Mbps

Required

bandwidth Mbps

Traffic in E by user

(mE)

Traffic in Mb by

month

Traffic in E Kbytes / hour

Model of traffic

Link Budget = Link Budget intends to estimate the system coverage by analyzing the

factors of the propagation of the forward signal and reverse signal, in order to obtain

the maximum propagation loss after certain communications quality is ensured.

Link Budget

KPIs

Accessibility = Capacity of the user to obtain a RAB

Retenibilidad = Capacity of the user to maintain the service required

Counter Detail

Rab active failures due to Iu for CS voice Falla en interfase Iu

Rab active failures due to radio int for CS voice Mala sincrona en interfase de radio

Rab active failures due to BTS for CS voice Desconexin por problemas en la BTS

Rab active failures due to Iur for CS voice Desconexin durante el proceso de seleccin de la DRNC

Rab active failures due to RNC for CS Voice Llamada cada por causas internas en la RNC

Number of RAB active failures caused by UE for CS

voice

UE no responde al mensaje de establecimiento de RRC

Mobility = Capacity of the operator to maintain mobility in all the network

Soft Handover = Several Radio Links active at the same time of different Nodes B. (the EU

changes of different Node B and in the same frequency).

Softer Handover = Special case of Soft handover where the radio links is added or removed on

the same Node B.

Hard Handover = This type of handover works under the concept of which all the Radio Links

assets (old) in the User Equipment are removed before establishing new Radio Link.

Hard Handover can be synchronous or non synchronous. The synchronization in

handover means that handover is not perceivable by user. Actually handover that he

requires a change of frequency (Inter frequency to handover) always is classified like

a Hard Handover.

IRAT Handover = This type of handover is considered like Hard Handover because it realises

between two technologies and it can be realised in both ways 2G-3G and 3G-2G

Blocking Rate = Congestion in the cell.

CCSR (Call Completation Success Rate) = Completation of successful calls

Report Radio Measurements Detail

Received total wideband power (RTWP) Total Noise Frequency Ul UTRA in the

antenna of the cell

Transmitted carrier power Total power TX in DL in the antenna of the cell

SIR (signal to interference ratio) Signal Stregth in UL (RSCP) between the signal

and mobile and the perceived interference

(ISCP)

RSCP Received Signal Code Power, is the power of

the signal by code

SIR error Difference between the intensity of signal

measured by the RNC servant and the intensity

of signal measured by the moving body

Transmitted code power It is the transmitted power of a cell for a

dedicated physical channel (DPCH) in Dl

Chip Energy Over noise (Ec/No) He is equivalent to the intensity of signal (SIR),

but based on measurements of the pilot

channel (CPICH) Common Pilot Chanel Control

Received Signal code power It is the received power that perceives the EU

UTRA received signal strength indicator (RSSI) It is the intensity of received signal that it

perceives the EU

Node B

Dedicated Measurements

UE

Channels

Physical Channel = information container (codes and phase)

Transport Channel = Characteristics of transmission

Dedicated Channel

Common Channel

Logical Channel = Specification of the information global content

Control Channel

Service Channel

Transport Channel = Dedicated Transport Channel

Dedicated Channel (DCH)

Common Channel Broadcast Channel (BCH)

Forward Access Channel (FACH)

Paging Channel (PCH)

Random access channel (RACH)

High-speed downlink shared channel (HS-DSCH)

Uplink

Downlink

Physical Channel

Downlink

Downlink dedicated physical channel (Downlink DPCH)

Downlink Common physical channel

Common Control Physical Channel (CCPCH)

Synchronization Channel (SCH)

Paging Indicator Channel (PICH)

Acquisition Indicator Channel (AICH)

Common Pilot Channel (CPICH)

High-Speed Packet Downlink Shared Channel (HS-PDSCH)

High-Speed Shared Control Channel (HS-SCCH)

Uplink Uplink Dedicated Physical Channel

Uplink Dedicated Physical Data Channel (Uplink DPDCH)

Uplink Dedicated Physical Control Channel (Uplink DPCCH)

High-Speed Dedicated Physical Channel (HS-DPCCH)

Uplink Common Physical Channel

Physical Random Access Channel (PRACH)

Clasification of Power Control

Uplink Power Control

Downlink Power Control

Open loop power control = estimates of the initial transmit power.

Closed loop power control = to rapidly adjust the power in

the uplink/downlink during the communication period.

inner loop power control = to converge the

received SIR to the target SIR by controlling the

transmit power of physical channels.

outer loop power control = to dynamically

adjust the SIR target value of the inner

loop control, so as to ensure that the

communication quality always meets the

requirements.

Open loop power control

Closed loop power control inner loop power control

outer loop power control

AMR Coding

The AMR speech codec produces a certain number of bits depending on the mode used. The speech

encoder output are put in order according to their subjective importance. This bit ordering can be utilized

for error protection purposes.

Class A contains the bits most sensitive to errors and any error in these bits would result in a corrupted speech frame which needs

error correction for proper decoding. It may be the only class

protected by a CRC.

Class B Classes B and C contain bits where increasing error rates gradually reduce the speech quality, but the decoding of an

erroneous frame can be done without significantly degrading the

quality. Class B bits are more sensitive to errors than Class C bits.

Class C

UE Modes and states

Idle Mode

Connected

Mode (RRC state)

Cell_DCCH = A dedicated physical

channel is allocated to the UE in

both the uplink and the downlink

Sets up the RRC connection on the

dedicated channel

Action

The UE uses the common transport

channel and then is converted to the

dedicated transport channel,

Cell_FACH = No dedicated transport

channel is allocated to the UE., the

UE continuously monitors a downlink

FACH channel.

Monitors an FACH.

Monitors the BCH channel of the

current serving cell

Transmits uplink control signaling and

small data packets on the RACH.

Initiates a cell update procedure when

the cell becomes another UTRA cell.

Cell_PCH = No dedicated channel is allocated

to the UE, the DRX technology is

adopted for the UE to monitor the

information transmitted on the PCH

channel at a specific paging time

slot.

Monitors the paging time slot based on the DRX period and receives the paging

messages transmitted on the PCH.

Monitors the BCH channel of the current serving cell

Initiates the cell update procedure when the cell changes.

URA_PCH = No dedicated channel is allocated to

the UE, the DRX technology is

adopted for the UE to monitor the

information transmitted on the PCH

channel at a specific paging time slot,

no uplink activity is allowed.

Monitors the paging time slot based on the DRX period and receives the paging

messages transmitted on the PCH.

Monitors the BCH channel of the current serving cell

Initiates the URA update procedure when the URA changes.

No resource is allocated for data transport in the URA_PCH state.

SHO System Handover

Active Set = Including all cells currently participating in a SHO connection of a UE

Monitored Set = Including all cells being continuously monitored by the UE and

which are not current included in its active set

Detected Set = Including the cells the UE has detected but are neither in the active set

nor in the monitored set

Process

Measurement

Decision

Execution

Measurement Control

Measurement execution and the result processing

The measurement report

Mainly accomplished by UE

Based on Measurement

The application and distribution of resource

Mainly accomplished by RRM in RNC

The process of signaling

Support the failure drawback

Measurement control refresh

Events of reporting

Intra-frequency events1A,1B,1C,1D,1F

Inter-frequency events 2D,2F,2B,2C

Inter-system events 3A,3C

Others6G,6F

1A A primary pilot channel enters the reporting range. When the active set of UE is full, UE stops reporting 1A

event.

1B A primary pilot channel leavels the reporting range.

1C The primary pilot channel in a non active set is better than the primary pilot channel in an active set

1D The best cell change

1E The measurement value of a primary pilot channel exceeds the absolute threshold

1F The measurement value of a primary pilot channel is lower than the absolute threshold

Intra-frequency events

2B The estimated quality value of the used frequency is lower than a certain threshold, and that of

the non-used frequency is higher than a certain threshold

2C The estimated quality value of the non-used frequency is higher than a certain threshold

2D The estimated quality value of the used frequency is lower than a certain threshold

2F The estimated quality value of the used frequency is higher than a certain threshold

Inter-frequency events

3A The estimated quality value of the used UTRAN frequency is lower than a certain threshold,

and that of the other system is higher than a certain threshold

3C The estimated quality value of the other system is higher than a certain threshold

Inter-system events

6G The time difference between downlink receiving and uplink transmission of the UE is shorter

than an absolute threshold

6F The time difference between downlink receiving and uplink transmission of the UE is bigger

than an absolute threshold

Others

Compresed Mode = Measure the inter-

frequency cell or inter-system

cell FDD mode

Downlink compressed = Since one receiver only

can work in one frequency, the UE has to stop

working if it is going to measure the signal from

another frequency cell. To ensure the dowlink

service unaffected, the remained data should be

sent in the limited time.

Uplink Compressed = UE should stop the uplink

transmission when the uplink working frequency is

very close to the measured frequency, for

example GSM 1800/1900 is very close to the

UMTS FDD uplink working frequency

SRNC/DRNC SRNC and DRNC are on a per connection basis between a UE and the UTRAN

The SRNC handles the connection to one UE, and may borrow radio resources of a certain cell from the

DRNC

Drift RNSs support the Serving RNS by providing radio resources

A UE in connection state has at least one and only one SRNC, but can has 0 or multiple DRNCs

CRNC The CRNC owns the radio resources of a cell

Dynamical control of power for dedicated channels, within limits admitted by CRNC, is done by the SRNC.

Scheduling of data for dedicated channels is done by the SRNC, while for common channels it is done by the

CRNC

Optimization

Single Site Verification = The single site verification is a part of the WCDMA network optimization to

ensure that the basic functions of the cell are normal, such as call access, call

quality, handover and so on

1. Checking warning

2. Checking the state of cell

3. Checking the parameters of radio access network

4. Checking the configuration: SC, Power

configuration, neighbor cell table, handovers

parameters

RF Optimization = Once all the sites in a given area are integrated and verified, RF optimization could

begin

1. Optimize CPICH, services coverage and best

server

2. Decrease the interference at the minimum level

3. Decrease the pilot pollution at the minimum level

4. Optimize neighbor cells table

5. Solve the call drop caused by RF

Parameters Optimization

1. Decrease the access success ratio scanner and UE

2. Decrease the call drop ratio RNC record data

3. Increase the quality of service Statistic tools and KPI

4. MSC & SGSN record if necessary

Parameters Adjusment Case

Data Analysis

Solution

GSM

Vs

WCDMA

Technology GSM GSM WCDMA

Frequency 800 MHz 1900 MHz 800 MHz

Frequencies Uplink 890-915 MHz 1850-1910 MHz

Frequencies Downlink 935-960 MHz 1930-1990 MHz

Wavelength 33 cm 16 cm

Bandwidth 25 MHz 60 MHz 5 MHz

Duplex Distance 45 MHZ 80 MHz N/A

Carrier Separation 200 KHz 200 KHz N/A

Radio Channels 125 300

Transmission Rate 270 Kbps 270 Kbps

Band (Telcel) B D,F B

Modulation GSMK GSMK QPSK

Access Method TDMA TDMA WCDMA

Data transmission 64 Kbps 64 Kbps

Release BSC R06B R06B N/A

Release RNC N/A N/A R99 y R5

Nodes MSC (MGw), BSC BTS MSC (MGw), BSC BTS Server (MGw), RNC Node B

Voice data transportes TDM/ATM TDM/ATM TDM/ATM/IP

Traffic Channels

different time slots are allocated to

different users

different time slots are allocated to

different users

different users are assigned unique

code and transmitted over the same

frequency band

Data GPRS/EDGE GPRS/EDGE HSDPA, HSUPA

STANDAR GSM GSM 3GPP

Time Slot 0.577 ms 0.577 ms N/A

RATE (Kbps) MODULATION

GSM 9.6 GMSK

HSCSD 14.4 GMSK

GPRS 21.4 GMSK

EDGE 69.2 8PSK

HSDPA 14 M 16QAM

HSUPA 1.4 M

DATA COMPARISON