Section 3 Page 1
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
Do not delete this graphic elements in here:
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMA UMTS Radio Principles
3JK10657AAAAWBZZA Edition 1
Section 3UTRAN scenarios
Section 3 Page 2
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 2
Blank Page
This page is left blank intentionally
Conversion into Alcatel-Lucent templateScholle, Martin2007-06-2003
RemarksAuthorDateEdition
Document History
Section 3 Page 3
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 3
Objectives
z To be able to build the map of the radio channels(logical, transport and physical channels) from a white paper.
Section 3 Page 4
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 4
Objectives [cont.]
This page is left blank intentionally
Section 3 Page 5
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 5
Table of Contents
z Introduction to UTRAN Scenariosz Introduction
z Radio Channels Mappingz Downlinkz Uplink
z Service Requestz System Information Collectionz RRC Connectionz IMSI Attachment & Location Updatez Paging
z RAB Establishmentz Admission Controlz Radio Bearer Establishment
z Mobility Management in Connected Modez Soft HO: Active & Monitoring Setz Soft HO: Eventsz Compressed Modez Hard HO: Events on other FDD
Frequenciesz Hard HO: Events on other GSM
Frequenciesz Exercises
z Scenario Descriptionz Downlinkz Uplink
Page
1 Introduction to UTRAN Scenarios 71.1 Introduction 8
2 Radio Channels Mapping 112.1 Downlink 122.2 Uplink 13
3 Service Request 143.1 System Information Collection 15
3.1.1 P-SCH & S-SCH 163.1.2 CPICH 173.1.3 System Information Broadcast 183.1.4 Procedure 203.1.5 Radio Channel Mapping: P-CCPCH 213.1.6 Cell Selection Principle 22
3.2 RRC Connection 233.2.1 UE Status 243.2.2 Procedure: RRC Connection Establishment 273.2.3 Procedure: RRC Connection: RRC Connection Release 283.2.4 How to contact UTRAN: the PRACH 29
3.3 IMSI Attachment & Location Update 313.3.1 Principles 323.3.2 Procedure: Direct Transfer 33
3.4 Paging 343.4.1 Procedure 1: UE in Connected Mode 353.4.2 Procedure 2: UE in Idle Mode 363.4.3 Paging: PICH & PCH Radio Channels 37
4 RAB Establishment 384.1 Admission Control 394.2 Radio Bearer Establishment 41
4.2.1 Signaling: RAB Establishment 424.2.2 Signaling: Radio Link Setup 434.2.3 Radio Bearer Mapping 444.2.4 Physical Layer Processing 454.2.5 Radio Channels 464.2.6 Radio Channels: Data Processing 474.2.7 Radio Channels: Transport Channel Multiplexing 484.2.8 Radio Channels: DPDCH/DPCCH Channels 49
5 Mobility Management in Connected Mode 505.1 Soft HO: Active & Monitoring Set 515.2 Soft HO: Events 525.3 Compressed Mode 535.4 Hard HO: Events on other FDD Frequencies 545.5 Hard HO: Events on other GSM Frequencies 55
6 Exercises 566.1 Scenario Description 576.2 Downlink 586.3 Uplink 59
Section 3 Page 6
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 6
Table of Contents [cont.]
Switch to notes view!
This page is left blank intentionally
Section 3 Page 7
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 7
1 Introduction to UTRAN Scenarios
Section 3 Page 8
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 8
1 Introduction to UTRAN Scenarios
1.1 Introduction
Iub
Serving RNC
CN Collection of System Information
System Information
RRC Connection
RRC Connection IMSI Attachment
IMSI Attachment
Paging
Paging
The UE is switched on !
How can it retrieve network parameters to request a service?
On the first part, we are going to see how a UE, after it is just switched on, can be able to request a service and to answer to a paging message.
So the first step is to retrieve information about the system. Thank to these system information the UE is able to attach its IMSI and to update its location to the Core Network.
After that the UE can monitor a channel to answer to a paging message or can request itself a service.
Section 3 Page 9
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 9
1 Introduction to UTRAN Scenarios
1.1 Introduction [cont.]
Iub
Serving RNC
CN
The UE requests a service.
How and in which conditions are the resources required setup ?
Admission Control
? RAB EstablishmentRAB
When a UE requests a service, the UTRAN must check if it has enough resources to establish new dedicated channels.
There are after signaling between the UE, the Node B, the RNC and the Core Network to provide to the UE the transfer of the data at the required QoS.
We will also how the data are mapped on the physical channels.
Section 3 Page 10
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 10
1 Introduction to UTRAN Scenarios
1.1 Introduction [cont.]
Iub
Serving RNC
CN
The UE uses a service and moves !
How UTRAN can provide the service despite the mobility ?
A new radio link is added Hard Handover on another FDD carrier Inter RAT Handover
BSCBTS
UTRAN must provide the transfer of the data at the requested QoS to a moving user. So different kinds of handover have been defined.
The Soft Handover, the UE can be linked to several cells using the same fraquency.
The Hard Handover inter FDD carrier and the interRAT HandOver between the 3G and the 2G network if the user loses the 3G coverage.
Section 3 Page 11
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 11
2 Radio Channels Mapping
Section 3 Page 12
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 12
2 Radio Channels Mapping
2.1 Downlink
Logical Ch.
Transport Ch.
Physical Ch.
AICHNot associated with transport channels PICH CPICH P-SCH S-SCH
PDSCH S-CCPCH P-CCPCHDPDCH + DPCCH
DTCH, DCCH CCCH, CTCH
DCH BCHPCHFACHDSCH
Not implemented yet in EvoliumTMSolution
PCCH BCCH
DPDCH and DPCCH multiplexed by time
Common Physical Ch.Dedicated Physical Ch.
Section 3 Page 13
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 13
2 Radio Channels Mapping
2.2 Uplink
Logical Ch.
Transport Ch.
Physical Ch.
PRACH PCPCHDPDCH + DPCCH
DTCH, DCCH CCCH
DCH1 RACHDCH2
CCTrCH
CPCH
DPDCH and DPCCH multiplexed by modulation
DedicatedPhysical Ch.
CommonPhysical Ch.
Section 3 Page 14
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 14
3 Service Request
Section 3 Page 15
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 15
3 Service Request
3.1 System Information Collection
PrinciplesThe UE synchronize itself at the slot on the P-SCH
UE synchronize itself at the frame level on the S-SCH and retrieve a group of 8 Scrambling codes.
The UE test the 8 SC on the CPICH to find the SC of the cell
The UE decode the BCH channel to read the system information
The UE select the best cell
Iub
Serving RNC
CN
???
Just after the switch on, the UE can decode only the P-SCH and S-SCH if it is on a covered area
Section 3 Page 16
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 16
3.1 System Information Collection
3.1.1 P-SCH & S-SCH
P-CCPCH Radio Frame 10 ms
Slot #0 Slot #1 Slot #14
acpP-SCH
S-SCH acs0
acp acpacs2 acs14
The SCH is time-multiplexed with the P-CCPCH (which carries the BCH) and consists of 2 sub-channels.
The Primary SCH (P-SCH) made of always the slot on all the FDD Cells. The UE uses it to acquire the slot synchronization to a cell.
The Secondary SCH (S-SCH) contains a sequence of 15 codes which identifies the Code Group of the Downlink Scrambling Code (DL SC) of the cell. The UE uses it to acquire the frame synchronization to a cell and to identify the Code Group of the DL SC.
256 chips
Cell Search Procedure (also called synchronization procedure)
z 3GPP TS 25.214 provides an informative description how it is typically done
z Step 1: slot synchronizationIn all the cell of any PLMN, the P-SCH is made of a unique & same primary code sequence of 256 chips repeated at each Time Slot Occurrence. This is typically done with a single matched filter (or any similar device) to the primary synchronisation code which is common to all cells. The slot timing of the cell can be obtained by detecting peaks in the matched filter output.
z Step 2: frame synchronization and code-group identificationA S-SCH is made of 15 repetitions of a secondary code sequence of 256 chips (one per Time Slot) transmitted in perfect synchronization with the P-SCH code sequences. The UTRAN uses 64 distinct secondary synchronization code sequences (reused in distant cells of the UTRAN). This is done by correlating the received signal with all possible secondary synchronisation code sequences, and identifying the maximum correlation value. Since the cyclic shifts of the sequences are unique the code group as well as the frame synchronisation is determined.
Each secondary code sequence corresponds to a unique group of 8 possible Primary Scrambling codes
z Step 3: (downlink) scrambling code identification} The UE determines the (primary) scrambling code used by the found cell through symbol-by-symbol
correlation over the CPICH (pilot) with all codes within the Code Group identified in the step 2 (8 possibilities).
} Afterwards the P-CCPCH can be detected and the system- and cell specific BCH information can be read.
Section 3 Page 17
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 17
3.1 System Information Collection
3.1.2 CPICH
CPICH (Common Pilot CHannel)
The pilot carries a pre-defined symbol sequence at a fixed rate.
It is a reference:
To aid the channel estimation at the terminal (time or phase reference)
To perform handover measurements and cell selection/reselection (power reference)
The UE tests the 8 DL SC of the Group Code. The DL SC which allows to retrieve the pre-define sequence is the DL SC of the cell.
Slot #0 Slot #1 Slot #14
Pre-defined symbol sequenceSF=256 Tslot=2560 chips 20 bits
The CPICH has the following characteristic
z The same channelization code is always used for the P-CPICH,z The P-CPICH is scrambled by the primary scrambling code,z There is one and only one P-CPICH per cell,z The P-CPICH is broadcast over the entire cell.
Section 3 Page 18
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 18
3.1 System Information Collection
3.1.3 System Information Broadcast
The broadcast system information:
May come from CN, RNC or Node-B.
Contains static parameters (Cell identity, supported PLMN types...) and dynamic parameters (UL interference level...).
Is arranged in System Information Blocks (SIB), which group together elements of the same nature.
Some exemple:SIB1: Core Network Information
SIB3: Cell Selection, Access Restriction
SIB7: UL Interference
SIB11: MeasurementCN
LA, RA
DL SC, Power Control info
UL interference level
Example of SIB:
z MIB: Master Info Block (structure & scheduling of SIBs)
z SIB 1: NAS System Information + Timer
z SIB 2: URA (not supported) +Timer
z SIB 3: Cell Selection/Reselection and Access Restriction
z SIB 5: Common channel Information (P-CCPCH, S-CCPCH, RACH) and AICH/PICH power offset
z SIB 7: UL Interference and PRACH parameter SIB 11:Measurements
z SIB 18:PLMN Identity of neighboring cells
Section 3 Page 19
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 19
3.1 System Information Collection
3.1.3 System Information Broadcast [cont.]
The broadcast system information can be carried on BCH which is transmitted permanently over the entire cell.
Transport Ch.
Logical Ch.
Physical Ch.
BCCH
BCH
P-CCPCH
The broadcast system information is made of 128 periodic radio frame. So its period is 1280 ms.
There are a Master SIB or MIB and several SIB (System Information Block) organised by domain.
Frame #0 Frame #1 Frame #2
Frame #i-1 Frame #i Frame #i+1
Frame #125 Frame #126 Frame #127
MIB SIB3 SIB11
SIB5 SIB7 MIB
SIB5SIB11 SIB7
Thanks to this channel, the UE is able to retrieve information allowing the request of a RRC connection like the Channelization code used on the uplink common channel
Three parameters are used to set the position of each SIB on the cycle.
SIB_POS: it is the position of the SIB on the cycle (#0 for the MIB for instance)
z SIB_REP: it is the repetition of the SIB on the cycle (the MIB is repeated several time on the cycle.z SIB_OFF: If one Radio Frame is not enough to send all the data for a SIB, the rest of the SIB can be send
on another radio frame. For example, 2 radio frame after the first one. It is the SIB_OFF.
Section 3 Page 20
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 20
3.1 System Information Collection
3.1.4 Procedure
System Information Update Request
Master/Segment Info Block(s), BCCH
modification time
Master/Segment Info Block(s)System Information (BCCH:BCH)
UE Node-B RNC
RRC RRC
NBAP
CN
Master/Segment Info Block(s)System Information (BCCH:BCH)
RRC RRC
Master/Segment Info Block(s)System Information (BCCH:BCH)
RRC RRC
System Information Update Response
NBAP NBAP
>> Why does RRC protocol >> Why does RRC protocol terminate at Nodeterminate at Node--B for B for
BCH (not at RNC)?BCH (not at RNC)?
NBAP
Section 3 Page 21
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 21
3.1 System Information Collection
3.1.5 Radio Channel Mapping: P-CCPCH
The Primary CCPCH carries the BCH, which provides system- and cell-specific information (e.g set of uplink scrambling codes)
The P-CCPCH is a fixed rate 30 kbps DL physical channel, which provide a timing reference for all physical channels (directly for DL, indirectly for UL).CCPCH is scrambled under the Primary Scrambling code.
Slot #0 Slot #1 Slot #13 Slot #14Slot #i
SCH
Tslot=2560 chips
20 bits
256 chips
Payload of 18 bits
The P-CCPCH is time multiplexed with the SCH which is transmitted during the first 256 chips.
P-CCPCH timing is identical to that of SCH and CPICH (see 3GPP 25.211).
The P-CCPCH contains no layer 1 information.
Even if the PCCPCH is not transmitted during the 256 first chips of each slot (SCH), the scrambling code is aligned with the PCCPCH frame boundary, i.e the first complex chip of the PCCPCH frame is multiplied with chip number zero of the scrambling code.
The Secondary CCPCH, which is used to carry FACH and PCH information, is scrambled under the Primary scrambling code as well.
Section 3 Page 22
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 22
3.1 System Information Collection
3.1.6 Cell Selection Principle
Now, the UE can read the BCH of one cell.
But this cell is not necessary the best because the SCH has been chosen randomly.
The UE compares the cells to be camped on the best one.
There are 2 criterion:
QRxLev, from the CPICH RSCP, to estimate the reception level.
Qqual, from the CPICH Ec/No, to estimate the quality of reception. It takes in account the interference level.
When a UE is not connected, like here, and is moving, it has to reselect regularly the best cell for itself. To protect some cells, it is possible to facilitate or not the selection of one cell.
Iub
RNC
CN
???
Aim : find a suitable cell to be camped on
The Cell selection criterion is defined in 3GPP TS 25.304 as:
z Squal>0 with Squal=Qqualmeas - Qqualminz Srxlev>0 Srxlev= Qrxlevmeas Qrxlevmin - Pcompensation
Parameters :
z Qqualmeas: defines the quality of the cell} Measured CPICH Ec/N0
z Qqualmin: defines the threshold for the quality of the cell} Configurable in each cell independently
} Range: -24 dB to 0 dB (step 1 dB)
z Qrxlevmeas : defines the cell Rx Level value} Measured CPICH RSCP
z Qrxlevmin : defines the minimum required RX level of the cell} Configurable in each cell independently
} Range: -115 dBm to -25 dBm
z Pcompensation:} Parameter to take in account the UE capacity
Section 3 Page 23
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 23
3 Service Request
3.2 RRC Connection
Why?The UE is switched on and has selected a cell.
The UE is in idle mode.
UTRAN doesnt know anything about this UE.
The UE has neither UTRAN identifier nor Scrambling and Channelization code.
The UE cant exchange any data with UTRAN.
To be known by UTRAN and to use dedicated radio resources, the UE has to be RRC connected.
After, the UE can attach its IMSI or update its location to the Core Network and can request a service
Iub
RNC
CN
RRC Connected
Section 3 Page 24
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 24
3.2 RRC Connection
3.2.1 UE Status
UE
detached
UE
in idle mode
UE
in connected
mode
RRC Connection Release
RRC Connection Establishment
out of coverage
just after switch on process
Including Cell search procedure
Just after the switch on, the UE has to attach its IMSI. Thanks to his procedure the Core Network knows, the UE is on the network and where it is located at the Location or routing area level.
Several sub-status in the connected
mode
To attach its IMSI and update its location the UE has to be in connected mode, so it has to request a RRC Connection
Just after switch on process contains:
z Cell selection (including cell search procedure) z PLMN selectionz Attachment procedure (see Appendix for more details)
The UE must enter the connected mode to transmit signalling or traffic data to the network
What is the relationship with the states of the mobile phone in GSM?
z The two GSM states, idle mode and connected mode, are similar to idle mode and cell_DCH state in UMTS.
What is the relationship with the states of the mobile phone in GPRS?
z There is no correspondence between GPRS states (idle, standby and ready) and UMTS states.
z Indeed there is no notion of connection on GPRS.
Section 3 Page 25
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 25
3.2 RRC Connection
3.2.1 UE Status [cont.]
Cell DCH
Cell FACH
URA PCH
Cell PCH
UE
in idle
mode
UE in connected mode
Cell_DCH state
Signalling and traffic data dedicated to the UE (mapped on DCCH and DTCH respectively) are carried on DCH transport channel
Cell_FACH state
Signalling and traffic data dedicated to the UE (mapped on DCCH and DTCH respectively) are carried on RACH (uplink) and FACH(downlink) transport channels
Cell_DCH Cell_FACHNo traffic UL/DL at expiry of timer
Cell_FACH Cell_DCHTraffic volume UL/DL too large
The initial state of the UE is determined by the DCCH established during RRC connection establishment:
z if the DCCH is mapped on a DCH, the UE is in cell_DCH statez if the DCCH is mapped on RACH/FACH, the UE is in cell_FACH state
The UE can move from one state to another during the time of the RRC connection.
z Transitions between states are: } based on traffic volume measurements and network load
} always triggered by UTRAN signalling
z Note: in cell_DCH state, the DSCH transport channel can also be used.
Section 3 Page 26
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 26
3.2 RRC Connection
3.2.1 UE Status [cont.]
Cell_PCH state
No transmission of signalling and traffic data dedicated to the UE (no DCCH and no DTCH)
But the RRC connection is still active (UTRAN keeps RNTI for UE) and UE location at a cell level.
- a DCCH (and possibly a DTCH) can be reestablished very quickly (this procedure is initiated by sending a paging signal PCH)
URA_PCH state
Very similar to cell_PCH state
UTRAN keeps the location of the UE at the URA level (set of UMTS cells)
Cell_PCH Cell_FACH URA_PCHToo many cell reselections
Cell_FACH Cell_PCHNo traffic UL/DL at expiry of timer 2
Cell/URA_PCH Cell_FACHIncoming DL or UL traffic
Cell DCH
Cell FACH
URA PCH
Cell PCH
UE
in idle
mode
UE in connected mode
URA: UTRAN Registration Area (a small set of cells)
Cell_PCH and URA_PCH states are needed for non real time services to optimise usage of codes and battery consumption. It would not be efficient to allocate permanently a DCH which would be used a very low percentage of time (Web application for example)
What is the difference between idle mode, Cell_PCH and URA_PCH states?
In idle mode the location of the UE is not known by the UTRAN, but only by the CN at a Location Area (LA) or Routing Area (RA) level (LA and RA and sets of cells larger than URA.
The paging message PCH must hence be sent in a LA or in a RA when the UE is in idle mode, whereas it only needs to be sent in a cell in Cell_PCH state or in an URA when the UE is in URA_PCH state (hence the paging procedure is much faster).
Section 3 Page 27
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 27
3.2 RRC Connection
3.2.2 Procedure: RRC Connection Establishment
Initial UE identity, Establishment cause, Initial UE capability
1. RRC Connection Request (CCCH:RACH)
UE
RRC RRC
3. Radio Link Establishment
Initial UE identity, RNTI, capability update requirement, TFS, TFCS, frequency, UL scrambling code, power control info
4. RRC Connection Setup (CCCH:FACH)RRC RRC
Integrity information, ciphering information
5. RRC Connection Setup Complete (DCCH:RACH or DCH)RRC RRC
2. Allocate RNTI, Select Level 1 and Level 2 parameters
(e.g. TFCS, scrambling code)
>> Can the UE send user information (e.g voice call) after compl>> Can the UE send user information (e.g voice call) after completing this stage?eting this stage?
Node-B RNC
1. UE initiates set-up of an RRC connection
z Initial UE identity: e.g TMSI z Establishment cause: e.g traffic class
2. RNC decides which transport channel to setup (RACH/FACH or DCH) and allocates
z RNTI (Radio Network Temporary Identity) and radio resources (e.g TFS, TFCS, scrambling codes) for this RRC connection.
3. A new radio link must be setup.
z This is done via a signalling procedure between RNC and Node-B which is managed by NBAP protocol (seeProcedure D for more detail).
4. Logical, transport and physical channel configuration are sent to the UE.
5. RRC Connection Setup Complete message is sent:
z on RACH in case of RRC connection on RACH/FACH (cell_FACH state)
z on DCH in case of RRC connection on DCH (cell_DCH state)
Section 3 Page 28
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 28
Node-B(DRNC)
SRNCDRNCNode-B(SRNC)
3.2 RRC Connection
3.2.3 Procedure: RRC Connection: RRC Connection Release
RRC RRC4. RRC Connection Release (DCCH:DCH )
Cause
RANAP RANAP
1. Iu Release Command
Cause
RANAP RANAP
2. Iu Release Complete
-
3. ALCAP Iu Bearer Release
RRC RRC5. RRC Connection Release Complete (DCCH:DCH )
-
6. Radio Link Deletion
7. Radio Link Deletion
8. Radio Link Deletion
UE CN
In this example, the UE is in macro-diversity on two Node-Bs from two different RNCs. Therefore the UE could only be in cell_DCH state (soft HO is only possible on DCH)
1. The CN initiates the release of RRC connection
2. -
3. SRNC initiates release of Iu Bearer using ALCAP protocol
4. -
5. -
6. SRNC initiates release of radio link (for Node-B of SRNC) using NBAP protocol
7. SRNC requires release of radio link (for Node-B of DRNC) to DRNC using RNSAP protocol
8. DRNC initiates release of radio link (for Node-B of DRNC) using NBAP protocol
Section 3 Page 29
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 29
3.2 RRC Connection
3.2.4 How to contact UTRAN: the PRACH
For the initial access, the UE has to use a common uplink channel called the PRACH
Every UE use this channel to request a connection. If 2 UEs request on the time there is collision, and UTRAN receives nothing.
To manage this problem, the UE sends a first message called preamble until it receives a response on a downlink channel called AICH.
After the response on the AICH, the UE sends its message (the request) on the PRACH.
Hello !
Iub
RNC
Preamble on the PRACH
Yes ! Response on the AICH
HELLO!I need a connection
Message part
PRACH= Physical Random Access Channel
AICH= Acquisition Indicator channel
Section 3 Page 30
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 30
3.2 RRC Connection
3.2.4 How to contact UTRAN: the PRACH [cont.]
The first preamble is sent with the power P.
The UE resends a preamble until it receives a response on the AICH.
At each time, it increases the power of the preamble by the Power Offset parameter (PO)
UTRAN cant receive its preamble if:
The power is not enough high
There is a collision with another user.
In the message part, there is the RRC connection request.
Preamble
Preamble
Message part
DPp,mPO
Reception of AICH
POP
PRACH channel
Section 3 Page 31
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 31
3 Service Request
3.3 IMSI Attachment & Location Update
HLR SGSNMSC/VLR
MSC/VLR SGSN
Iub
RNCThe UE has selected a cell.
It had to declared its identity and its location (LA & RA) to the Core Network.
So, it requests a RRC connection to send to the Core Network information about its situation.
The parameters are mainly the LA, the RA and its IMSI
Initial Attachment
In the selected PLMN, the UE:
z selects the best cell according to radio criteria I
z initiates attachment procedure on the selected cell
During the attachment procedure (called IMSI attach for CS domain, GPRS attach for PS domain), the UE indicates its presence to the PLMN for the purpose of using services:
z authentication procedure
z storage of subscriber data from the HLR in the VLR (or in the SGSN for PS domain)
z allocation of the TMSI (P-TMSI for PS domain)
The result of the procedure is notified to the UE:
z if successful, the UE can access services
z if it fails, the UE can only perform emergency calls
LA=Location Area= Set of cells for the CS CN
RA= Routinf Area= Set of cells for the PS CN
Section 3 Page 32
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 32
3.3 IMSI Attachment & Location Update
3.3.1 Principles
When camping on a cell, the terminal must register its LA and/or its RA.
When the terminal moves across the network, it must update its LA (RA) which is stored in VLR (SGSN) in the Core Network.
LA (RA) Update is performed periodically or when entering a new LA (RA).
HLRSGSNMSC/VLR
Location Area (LA)
Routing Area (RA)
MSC/VLR SGSN
LA and RA are managed on an independent way, but a RA must always be included in one LA (and not be divided into several different LAs).
z LA update is performed by the NAS layer MM (Mobility Management) located in UE and in MSC. z RA update is performed by NAS layer GMM (GPRS Mobility Management) located in UE and in SGSN.
In the Core Network, the location information is stored on databases:
z HLR (Home Location Register)} It stores the master copy of users service profile, which consists of information on allowed services,
forbidden roaming areas, and which is created when a new user subscribes to the system.
} The HLR also stores the serving system (MSC/VLR and/or SGSN) where the terminal is located.
z VLR (Visitor Location Register)} It serves the terminal in its current location for CS services and holds a copy of the visiting
} users service profile.
} It stores the Location Area (LA) where the terminal is located.
z SGSN (Serving GPRS Support Node)} It serves the terminal in its current location for PS services and holds a copy of the visiting
} users service profile.
} It stores Routing Area (RA) where the terminal is located.
Section 3 Page 33
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 33
3.3 IMSI Attachment & Location Update
3.3.2 Procedure: Direct Transfer
RANAP RANAP1. Direct Transfer
CN Domain Indicator, NAS PDU
RRC RRC
2. Downlink Direct Transfer (DCCH:FACH or DCH)
NAS message
UE Node-B SRNC CN
Use mainly for the IMSI attachment, location update and the authentification between the UE and the Core Network
RANAP RANAP2. Direct TransferCN Domain Indicator,
NAS PDU
RRC RRC
1. Uplink Direct Transfer (DCCH:RACH or DCH)
CN node indicator, NAS message
UE must be in cell_FACH or in cell_DCH states.
Section 3 Page 34
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 34
3 Service Request
3.4 Paging
Core Network
Called number
HLRMSC/VLR MSC/VLR
Location Area
Some one is calling me, I request a RRC
connection
Principle
Paging message with the IMSI of the
called UE
Iub
RNC
Iub
RNC
Iub
RNC
If the UE is in idle mode. UTRAN doesnt know them and can just forward the paging message coming from the Core Network to all the cell belonging to the Location ou Routing Area.
The UE monitors periodically a channel to check if it is paged or not.
If the UE is connected the Core Network knows the Serving RNC of the UE and sends the paging message just to this RNC.
The RNC knows the UE uses the dedicated or common channel to send the paging message.
Section 3 Page 35
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 35
3.4 Paging
3.4.1 Procedure 1: UE in Connected Mode
RANAP RANAP1. Paging
CN Domain Indicator, UE identity, Paging cause
RRC RRC2. Paging Type 2 (DCCH:FACH or DCH)
In this case the UE is already connected and is using a service (voice call, web-browsing ). The Core Network knows the situation of the UE and mainly its Serving RNC. The CN contacts directly the Serving RNC.
The RNC doesnt use the PCCH and the PCH but the channel used for the UE, dedicated or common, according to the status of the UE.
UE Node-B SRNC CN
UE is in cell_FACH or in cell_DCH states:
1. CN initiates the paging of a UE to Serving RNC
2. Paging of UE with Paging Type 2 (on DCCH) using the existing RRC connection
Section 3 Page 36
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 36
3.4 Paging
3.4.2 Procedure 2: UE in Idle Mode
RRC RRC2. Paging Type 1 (PCCH:PCH)
RRC RRC2. Paging Type1 (PCCH:PCH)
RANAP RANAP1. Paging
CN Domain Indicator, UE identity, Paging cause
RANAP RANAP1. Paging
Idem
When the is in idle mode, UTRAN doesnt know where it is located and the Core Network knows its location at the LA or RA level. UTRAN uses the PCCH and the PCH radio channels.
UE 1 Node-B1UE 2 Node-B2 RNC1 RNC2 CN
UE is in idle mode:
1. CN initiates the paging of a UE over a LA (RA in PS domain) spanning, for example, two RNCs.
2. Paging of UE with Paging Type 1
LA: Location Area, RA: Routing Area (see subchapter 5.8 Mobility Management)
A similar procedure applies to UE in cell_PCH or in URA_PCH states.
Section 3 Page 37
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 37
3.4 Paging
3.4.3 Paging: PICH & PCH Radio Channels
The UE doesnt watch the S-CCPCH.
It watches the PICH (Page Indicator Channel) at regular and defined interval and look for its PI, for Paging Indicator.
The PI is based on the IMSI. Several UEs can have the same PI.
When the UE find its PI on the PICH, it watches the S-CCPCH to check if it is for it and what is the cause.
Then it requests on RRC connection to have a RAB.
Transport Ch
Iub
RNC
PICHS-CCPCH
PCH
PCCH Logical Ch
Physical Ch
MAC
Physical layer
In RNC
In Node B
PICHS-CCPCH
Paging message
PI
PI
PI
...
The period of the cycle is between 4 and 4096 radio frames. That means the UE can monitor the PICH every X seconds, with X between 40 ms and 40,96 seconds. If the period is too short the UE uses too much power if the period is 40 s, the delay is really long.
It is a trade-off between the delay and the consumption.
To determine the radio frame number into the cycle and the Paging Indication, the UE uses its IMSI and others parameters send on the SIB.
Section 3 Page 38
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 38
4 RAB Establishment
Section 3 Page 39
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 39
4 RAB Establishment
4.1 Admission Control
According to the previous part WCDMA in UMTS, if the interference level at the Node B level is too high, the Node B cant decode all the signal. The size of the cell decreases. The interferences are due to several causes:
The radio environment and the load of the adjacent cells,
Some users use too much power, the power control manages this problem,
There are too many users on the the cells
UTRAN has to check if there is enough UL radio resource
Iub
RNC
f
P
ISCP = NoSIR
PG
Eb
RSCP = Ec
At Node B reception level
SIR too small to retrieve the message
2 others questions before adding a new user : Is there sufficient DL radio resource andsufficient processing resources ?
If the RAC has not been passed,
z For CS services, the call cant be established.z For PS services, the UTRAN may try assigning a RB with a lower bit rate. There are different level of bit
rates than can be used a given requested RAB. The Node B tries to assign first the highest, and then goes to the lower rates, as long as the RAC rejects the Radio Link Reconfiguration.
Section 3 Page 40
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 40
4 RAB Establishment
4.1 Admission Control [cont.]
Is there sufficient UL Radio Resource -> Rx RAC
If UL interference level + estimated new user contribution < threshold
Then Rx RAC ok
Is there sufficient DL Radio Resource -> Tx RAC
If Total DL Tx Power + estimated new user contribution < threshold
Then Tx RAC ok
Is there sufficient processing resource -> Processing RAC3 main points are checked:
the channelization codes
The DSP (in BBs) load
The number of user and radio links limited respectively to 64 users and 90 RLs
RAC = Radio Access Control
Section 3 Page 41
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 41
4 RAB Establishment
4.2 Radio Bearer Establishment
We have seen how a UE, after the switch on, can collect system information, update its location, request a RRC Connection and a service, can be paged and how UTRAN allows it to use services. Now how is established the RAB ?
Signaling
Core NetworkIub
Node B
RNC
UTRAN
RAB
Radio Bearer
Logical Channel
RLC
Transport Channel
MAC
Physical Channel
Phy.
RLC Mode: Tr., UM or AM and retransmission parameter for AM
TTI, TFS, TFCS, CRC, FEC, Coding Rate, Rate Matching
Frequency, Power, Channelization & Scrambling codes
RRC
Configured by
Iu Bearer RAB
RAC = Radio Access Control
Section 3 Page 42
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 42
4.2 Radio Bearer Establishment
4.2.1 Signaling: RAB Establishment
RANAP RANAP1. RAB Assignment Request
RAB parameters, User plane mode, Transport Address, Iu
Transport association
2. ALCAP Iu Data Transport Bearer Setup
3. Radio Link Establishment
RRC RRC4. RB Setup (DCCH:FACH or DCH )
TFS, TFCS...
RRC RRC5. RB Setup Complete (DCCH:RACH or DCH )
-
RANAP RANAP6. RAB Assignment Response
-
The UE is RRC connected and has requested a service.
UE Node-B SRNC CN
Can the UE send user information (e.g voice call) just after Radio Access Bearer establishment?
YES : At the end of this signaling procedure, a RAB has been assigned to the UE to carry user information. The RAB is mapped on the RB which has been set up. The RB is mapped on DTCH: RACH/FACH or DCH.
Section 3 Page 43
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 43
4.2 Radio Bearer Establishment
4.2.2 Signaling: Radio Link Setup
Cell id, TFS, TFCS, frequency, UL scrambling code, power control info
Radio Link Setup RequestNBAP NBAP
Signaling link termination, transport layer addressing info
Radio Link Setup ResponseNBAP NBAP
Downlink synchronisationIub-FP Iub-FP
Uplink synchronisationIub-FP Iub-FP
Start RX
Start TX
>> Are NBAP, ALCAP and RRC messages carried on the same transpor>> Are NBAP, ALCAP and RRC messages carried on the same transport bearers on Iub?t bearers on Iub?
ALCAP Iub Data Transport Bearer Setup
Node-B SRNC
RAC = Radio Access Control
This procedure is used in many RRC procedures, e.g RRC connection establishment (Procedure C1), Radio Bearer Set-up (Procedure F1), soft HO (Procedure G)
In this procedure:
z a radio link is set up by the RNC on the Node-B side using the NBAP protocol
z (a similar task is performed on the UE side using RRC protocol, see e.g. procedure C1)
z a terrestrial link (AAL2 bearer) is setup on Iub interface using ALCAP protocol
Section 3 Page 44
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 44
4.2 Radio Bearer Establishment
4.2.3 Radio Bearer Mapping
We have seen how a UE, after the switch on, can collect system information, update its location, request a RRC Connection and a service, can be paged and how UTRAN allows it to use services. Now how are established the RAB ?
Core NetworkIub
Node B
RNC
UTRAN
RAB
Radio Bearer
Logical Channel
RLC
Transport Channel
MAC
Physical Channel
Phy.
RLC Mode: Tr., UM or AM and retransmission parameter for AM
TTI, TFS, TFCS, CRC, FEC, Coding Rate, Rate Matching
Frequency, Power, Channelization & Scrambling codes
RRC
Configured by
Iu Bearer RAB
RAC = Radio Access Control
Section 3 Page 45
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 45
4.2 Radio Bearer Establishment
4.2.4 Physical Layer Processing
Convolutional coding, Turbo coding
10 ms frame duration15 time slots
CCtrCH
DPDCH, DPCCH, PRACH...
Channelization codesScrambling codes
QPSK
Channel Coding
Radio Frame Segmentation
Transport Channel Multiplexing
Physical Channel Mapping
Spreading
Modulation
Physical Channels spread over 5 MHz bandwidth
Layer 1
The physical layer belongs to control plane and to user plane.
Physical layer main functions:
z Multiplexing/de-multiplexing of transport channels on CCTrCH (Coded Composite Transport Channel) even if the transport channels require different QoS.
z Mapping of CCTrCH on physical channels
z Spreading/de-spreading and modulation/demodulation of physical channels
z RF processing (3 GPP 25.10x)
z Frequency and time (chip, bit, slot, frame) synchronization
z Measurements and indication to higher layers (e.g. FER, SIR, interference power, transmit power, etc.)
z Open loop and Inner loop power control
z Macro-diversity distribution/combining and soft handover execution
Section 3 Page 46
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 46
4.2 Radio Bearer Establishment
4.2.5 Radio Channels
Assuming a UE a video call service. What happens in Uplink ?
RLC
MAC
Physical Layer
Radio Bearer
Logical Ch. DTCH
Transport Ch. DCH
Physical Ch. DPDCH/DPCCH
RLC parameters
RAB :64 kbps
MAC parametersMode : Transparent because it is a real time service
CRC = 16 bits, FEC = Turbo Code Coding Rate = 1/3, TTI= 20 ms, TFS=(0*640, 2*640 bits)
640
640
640
640
640
640
TTI
How many radio frame are necessary to send all this data ?
CN
UE
The RB 20 (1st column ) corresponds to the Video Call.
Section 3 Page 47
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 47
4.2 Radio Bearer Establishment
4.2.6 Radio Channels: Data Processing
Assuming a UE a video call service. What happens in Uplink ?
#1 #2
#1 #2
Transport Blocks
CRC attachment
Tr Bl concatenation
Turbo coding (1/3)
Tail Bit Attachment
1 st interleaving
Radio Frame Segmentation
Rate matching
640 bits 16
(640+16)*2=1312 bits
1312*3=3936 bits
1312*3=3936 bits6
3942 bits
#1 #21971 1971
#1 #21971 +Nrm 1971 +Nrm
Can you deduce the SF ?
And the value of Nrm ?
First, the 16 CRC bits are added at each transport block.
Then the transport block are concatenated.
The turbo coding consist of adding a lot of redundant bits to be able to detect and correct errors.
Before the interleaving some bits are added. The purpose of the interleaving is to avoid to have big packet of errors at the reception.
Finally the data are segmented by 2, because the TTI=20 ms and a radio frame is 10 ms.
At the end to fill the radio frame, Nrm bits are added.
Section 3 Page 48
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 48
4.2 Radio Bearer Establishment
4.2.7 Radio Channels: Transport Channel Multiplexing
Assuming a UE a video call service and on the same time sends on a e-mail.
How can it be possible to send 2 different services on the same physical channel ?
Several transport channels can be time-coordinated to be multiplexed on a CCTrCHbefore mapping on one physical channel
MAC
TFC Selection
L1
TrCH Multiplexing
Phy. Ch. Mapping
CCTrCH
Physical Channel
DCH1 DCH2
Example:
TFS (DCH1)={(0*640); (4*640)}
TFS(DCH2)={(1*0); (1*39); (1*42); (1*55); (1*65)}
TFCS={(0*640); (1*0)}; {(0*640); (1*39)}; {(0*640); (1*42)}; {(0*640); (1*55)}; {(0*640); (1*65)}; {(1*640); (1*39)}; {(1*640); (1*42)}
MAC selects TFC inside TFCS.
There is one TFCS per CCTrCH
Transport Format
Transport Format Combination
TFS= Transport Format Set
TFCS=Transport Format Combination Set
TF=Transport Format
Section 3 Page 49
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 49
4.2 Radio Bearer Establishment
4.2.8 Radio Channels: DPDCH/DPCCH Channels
Uplink
Downlink
Slot #0 Slot #1 Slot #13 Slot #14Slot #i
Slot #0 Slot #1 Slot #13 Slot #14Slot #i
Data : user data, RRC Signaling & NAS Signaling DPDCH
DPCCH Pilot TFCI FBI TPC
Multiplexed by the modulation
Data1 TPC Data2 TFCI Pilot
DPDCH DPCCH DPDCH DPCCH DPCCH
Time-multiplexed
Why are DPDCH and DPCCH time-multiplexed in DL(and not transmitted simultaneously as in UL)?
Discontinuous transmission can cause audible interference to audio equipment close to the terminal (e.g hearing aids), which is a disturbance for user.
In UL the transmission is always continuous, because there is at least the DPCCH which is transmitted. The user will not be disturbed.
In DL the transmission may be discontinuous, but it is no problem (no user at the base station).
Note: The downlink DPDCH/DPCCH physical channels are called the DPCH physical channel.
Section 3 Page 50
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 50
5 Mobility Management in Connected Mode
Section 3 Page 51
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 51
5 Mobility Management in Connected Mode
5.1 Soft HO: Active & Monitoring Set
Iub
RNC
The RNC manages the Active Set and builds the Monitoring Set.
The Monitoring Set is built from the information of topology and design in the RNC.
The Active Set is managed from the event send by the UE to the RNC.
Cell in the Active Set
Cell in the Monitoring Set
The maximum number of cells in the monitoring set is 32.
The maximum number of cells in the active set is set from the Office Data, between 3 and 6.
The monitored set is built for each UE by the RNC from the neighboring list. The RNC selects the best cells in this list for the monitored cells.
Section 3 Page 52
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 52
5 Mobility Management in Connected Mode
5.2 Soft HO: Events
Iub
RNC
There are 3 events for the soft handover. The value measured is the CPICH Ec/No.
The event 1a is triggered when the CPICH Ec/No of a monitored cells is above a certain threshold.If the event is fulfilled the cell is added in the active set
The event 1b is triggered when the CPICH Ec/No of a active cell is below a certain threshold.If the event is fulfilled the cell is removed from the active set
The event 1c is triggered when the active set has reached its maximum size and the CPICH Ec/No of a monitored cells is better than a cell belonging to the active set.If the event is fulfilled the candidate cell replaces the cell in the active set Cell in the Active Set
Cell in the Monitoring Set
The simplified formula to trigger an 1a event is :
z 10log(Mnew) > 10log (MBest) R1a
Where:
z Mnew is a measurement on the candidate cell about the quality of reception.z Mbest is a measurement on the best cell in the active set about the quality of reception.z R1a is the Reporting Range.
Best Cell
T1 -> Event 1a
R1a
CPICH Ec/N0
TimeCandidate
Cell
T0
Section 3 Page 53
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 53
5 Mobility Management in Connected Mode
5.3 Compressed Mode
Iub
RNC
Cell in the Active Set
Cell in the Monitored Set, same FDD frequency
Cell in the Monitored Set, other FDD frequency
Cell in the Monitored Set, GSM cell
Most of the UEs are not dual receivers. And they need to perform measurements on other frequencies.
So UTRAN has to free it time window to perform these measurements on other FDD frequencies or on GSM frequencies.
The main method is to divide the SF of certain frame by 2, so it divides the length of the frame by 2.
Time interval to measure other frequencies
Compressed mode method available according to the 3GPP TS 25.212
z compressed mode methods:} By puncturing : the rate matching is applied for creating a transmission gap in one or two frames
(not in UL)
} Reducing the SF by 2
} Compressed frames can be obtained by higher layer scheduling. Higher layers then set restrictions so that only a subset of the allowed TFCs are used in a compressed frame. The maximum number of bits that will be delivered to the physical layer during the compressed radio frame is then known and a transmission gap can be generated
Section 3 Page 54
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 54
5 Mobility Management in Connected Mode
5.4 Hard HO: Events on other FDD Frequencies
Iub
RNC
Cell in the Active Set
Cell in the Monitored Set, same FDD frequency
Cell in the Monitored Set, other FDD frequency
Cell in the Monitored Set, GSM cell
There are 4 events to watch the UMTS cell with other FDD frequencies
The event 2d_cm is triggered when the quality of on the current frequency is below a certain quality. The compressed mode is launched.
The event 2b is triggered when the quality of the current frequency is belowa certain threshold and the quality on an other frequency is above a certain threshold
The event 2f is triggered when the quality on the current frequency is above a certain threshold. The compressed mode is deactivated.
Section 3 Page 55
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 55
5 Mobility Management in Connected Mode
5.5 Hard HO: Events on other GSM Frequencies
Iub
RNC
Cell in the Active Set
Cell in the Monitored Set, same FDD frequency
Cell in the Monitored Set, other FDD frequency
Cell in the Monitored Set, GSM cell
2 causes can trigger an hard HO toward the GSM system:
Some bad radio conditions
due to the service requested
The event 2d_cm is triggered when the quality of on the current frequency is below a certain quality. The compressed mode is launched.
The event 3a is triggered when the quality on the current FDD frequency is below a certain threshold and the quality on the GSM is above another threshold.
The event 3c is triggered when the service requested can be managed by the GSM, the voice typically.
Section 3 Page 56
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 56
6 Exercises
Section 3 Page 57
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 57
6 Exercises
6.1 Scenario Description
Objectives:Rebuilt the channels mapping, Logical, Transport and Physical channelsfrom a scenario to guide you with the 2 next pages
Scenario:
The UE switches on in a covered area
The UE collects information about the system
The UE requests a RRC connection to declare its location and releases the RRC connection
The UE receives a paging message to receive an e-mail
UTRAN establishes a RAB and is in the DCH_Cell State
As the traffic is not large, the UE passes to the FACH_Cell State
Be careful, following this scenario, some channels are missing.Which are the missing channels ?
Section 3 Page 58
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 58
6 Exercises
6.2 Downlink
Logical Ch.
Transport Ch.
Physical Ch.
Section 3 Page 59
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 59
6 Exercises
6.3 Uplink
Logical Ch.
Transport Ch.
Physical Ch.
Section 3 Page 60
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 60
Evaluation
Thank you for answeringthe objectives sheet
Objective: To be able to build the map of the radio channels (logical, transport and physical channels) from a white paper.
Section 3 Page 61
All rights reserved 2007, Alcatel-Lucent3JK10657AAAAWBZZA Edition 1
All rights reserved 2007, Alcatel-LucentAlcatel-Lucent W-CDMAUMTS Radio Principles
UTRAN scenarios 3 61
End of Module
Top Related