Timing Parameter v2

1 © 2005 Nokia

Company Confidential

Engineering Support Service –Network Performance Consultancy

Timing ParameterT300 N300T312 N312T313 N313T314 T315 N315

November 28, 2006Consultancy & Integration, Taiwan

2 © 2005 Nokia


T300 N300

3 © 2005 Nokia


Parameter Setting (T300, N300)

4 © 2005 Nokia


RRC Setup & Access Phase T300_N300UE Node B RNC

ALCAP:ERQ

ALCAP:ECF

NBAP: Synchronisation Indication

[DCH] RRC: RRC Connection Setup Complete

L1 Synchronisation

BTS Starts sending DPCCH: Pilot and TPC & Starts UL synchronization

procedure

Start TX/RX

Start TX/RX

UE start sending DPCCH for UL sync purposes (pilot) after DL sync is established

RNC sends RRC Connection Setup -message

RNC starts timers T_RRC_Resp_CCH (6 s),

[FACH] RRC: RRC Connection Setup

NBAP: RL Setup Response

BTS sends: NBAP RADIO LINK SETUP

RESPONSE -message

UE sends RRC Connection Request -message

Timer T300= 2s is started

[RACH] RRC:RRC Connection Request

S

NBAP: RL Setup RequestNBAP:RL Setup Request

RNC receives RRC Connection Request and starts buffering timer N300 (3) *T300 ( 2s)

NEMO

Wei Yun

Note

N300 - no. of RRC Conn Request resend T300 - interval between 2 RRC Conn Request

Wei Yun

Note

ERQ = Establish Request ECF = Establish Confirm establish Iub connection

Wei Yun

Note

NBAP: Radio Link Setup Request includes UL and DL configuration data for the radio link that the Node B is being requested to support

Wei Yun

Note

TPC - Transmit Power Control The UE (User Equipment) and Node B generate TPC (Transmit Power Control) commands to control each others transmit power. This information is sent in the TPC field of the DPCCH (Dedicated Physical Control Channel). TPC commands are send 1500 per second. TPC=0, decrease power TPC=1, increase power

Wei Yun

Note

if N300*T300 expired, RRC connection establishment aborted and UE return to idle mode

Wei Yun

Note

if RNC reply an RRC reject message, need to wait for timer RNC: WaitTimeRRC (depends on service requested) expired then only can resend request message or enter idle mode if max number of attempts has been reached.

Wei Yun

Note

hardcoded parameter in RNC - timer starts when RNC initiates RRC procedure in common channel - timer stops when receive MS response message regarding the on-going RRC procedure

5 © 2005 Nokia


T312 N312

6 © 2005 Nokia


Parameter Setting (T312, N312)

Wei Yun

Note

The RNC checks that the radio links in the active set of the UE are synchronised by setting a radio link-specific "in sync"/"out of sync" status based on the indications received from BTS.

7 © 2005 Nokia


RNC receives RRC Connection Setup Complete –message ->

RRC Connection Setup Complete –message SENT after PC preamble & sRB delay TSLs from DL sync is achieved

L1 Synchronization established

BTS sends NBAP: SYNCHRONIZATION

INDICATION -message

UE initiates physical dedicated channel establishment before sending e.g. RRC Connection Setup Complete –message on DPDCH

Timer T312 started

“in sync”indicators on L1

Timer T312=6s stopped

N312=4 L1 “in sync” indicators

L1 Synchronization

established

N_INSYNC_IND =8 (80 ms) indicators on L1

Other cases HHO, FACH=>DCH-state transitions

1

RRC Setup & Access Phase T312_N312

UE starts to send UL DPCCH, PC preamble & sRB-delay amount of DPCCH frames

PC preamble & sRB-delay amount of DPCCH frames sent by UE

UE Node B RNC

ALCAP:ERQ

[DCH] RRC: RRC Connection Setup Complete

L1 Synchronisation

Start TX/RX

[FACH] RRC: RRC Connection Setup

NBAP: RL Setup Response

[RACH] RRC:RRC Connection Request

NBAP: RL Setup Request

NBAP: Synchronisation Indication

Start TX/RX

1

2

2

33

4

4

Wei Yun

Note

N312 - no. of in sync indicators received T312 - time frame to receive in sync indicators interval between in sync indicators = 10ms

Wei Yun

Note

The RRC Connection Setup message also provides timing information so the UE has some knowledge of when to expect the start of the downlink frame and slot structure

Wei Yun

Note

L1 of the Node B generates in-sync primitives whenever it judges itself to have successfully received a DPCCH frame. If the Node B receives NInSynchInd (8) successive (not necessarily consecutive) in-sync primitives then it sends a Synchronisation Indication message to the RNC to indicate that the DPCH has been established and that the Node B has moved from the initial state to the in-sync state.

Wei Yun

Note

pc-preamble and sRB-delay are part of the parameters transmitted in RRC Connection Setup message and used by UE to set DPCH initial output power and to use for power control. The number of DPCCH radio frames UE transmitted is instructed by the parameter pc-preamble within the RRC Connection Setup message. The UE then transmits a further DPCCH radio frames where the number of frames is instructed by the parameter sRB-delay within the RRC Connection Setup message. Having transmitted the above DPCCH radio frames, the UE transmits the RRC Connection Setup Complete message on the newly established DCH. While UE has been transmitting these DPCCH radio frames, the Node B has been attempting to achieve the UL synchronisation.

Wei Yun

Note

"in sync" indicator => CPHY-Sync-IND

Wei Yun

Note

hardcoded parameter in Node-B: N_INSYNC_IND

8 © 2005 Nokia


Each Sync time of UE and BTS

• First CPHY-Sync-IND need after 160 ms achieving the DPCH establishment

• Every frame = 10 ms

• If N312 =1 around 170 ms

• If N312 =4 = around 200 ms

• If N312 =100 = around 1160 ms

• If N312 = 400 = around 4160 ms

• So, the each Sync time of UE and BTS is “10 ms”

Use NEMO for test

9 © 2005 Nokia


T313 N313 N315 T314 CS Call

10 © 2005 Nokia


Parameter Setting (T313, N313, N315, T314)

11 © 2005 Nokia


• Radio link failure detection in DL is based on counter N313 (counting “out of sync”indicator) and timer T313 in UE

• In CELL_DCH State, after receiving N313 consecutive "out of sync" indications from layer 1 for the established DPCCH physical channel in FDD the UE

• start timer T313

• upon receiving N315 successive "in sync" indications from layer 1 and upon change of UE state:• stop and reset timer T313

“out of sync” indicators

Timer T313 (8 s) started

“in sync ”indicators on L1

N315=2 (20 ms) L1 “in sync” indicators

N313 ( 50, 500 ms) amount of “out of sync”indicators

Timer T313 stopped and reset

Dropped RABs – RAB_ACT_FAIL_VOICE_RADIO

Wei Yun

Note

when UE receive BLER > 20% => estimate to be out of sync

Wei Yun

Note

N313 - no. of out of sync indicators T313 - after N313 achieved, time to wait before declare RL failure (only RL release but Iu still remain) N315 - no. of in sync indicators after T313 started, after achieved N315, T313 stopped T314 - after RL failure (means T313 expired), time to wait before RNC send Iu Release Request to CN (this is not used currently)

12 © 2005 Nokia


“out of sync” indicators

Timer T313 started

N313 amount of “out of sync” indicators

Timer T313 expires

Radio Link Failure T314 value is checked, T314 = 0s in current release

No re-establishment for RT services in current release

Timer T_RLFAILURE started

N_OUTSYNC_IND “out of sync” indicators = 8

Timer T_RLFAILURE expires = 2s

RNC receives NBAP:RADIO LINK

FAILURE –message form BTS with a cause

value "Synchronization

Failure"

T_L1_Sync_ReEstab_Wait –timer started in RNC = 2s

T_L1_Sync_ReEstab_Wait –timer expired

The Iu release request with a cause value ‘Failure in Radio Interface

Procedure’ is sent to the CN,

RT

T314 value is checked, T314 = 0s in current release

re-establishment for RT services=0

RT RBs released locally

RT

BTS NBAPUE

UE loses radio connection

MS is in CELL_DCH state

NBAP:RADIO LINK FAILURE

Loss of L1 sync. detected timer

T_RL_Failureexpires

Timer T_L1_Sync_ReEstab_Wait –timer started in RNC =2s expires

T314=0 => UE releases RT bearers locally;

T314=0 => RNC sends an Iu Release Request to the CS-CN;

RNC MGW

Iu Release Request

Iu Release command

RRC connection release

Dropped RABs – RAB_ACT_FAIL_VOICE_RADIO

1

1

2

2

3

3

4

4

Wei Yun

Note

hardcoded parameter in Node-B: N_OUTSYNC_IND T_RLFAILURE hardcoded parameter in RNC: T_L1_Sync_REstab_Wait

13 © 2005 Nokia


T314=0 - AMR Transaction lost due to radio failure (out-of-sync)(Global)

Network View

T_L1_sync_re_estab = 2s

T_L1_Sync_ReEstab_Wait = 2 s

14 © 2005 Nokia


NEMO_Dropped RABs

“out of sync” indicators N313 amount of “out of sync” indicators

Timer T313 expires RT RBs released locally

Wei Yun

Line

if a lot of MR, it might be out of sync due to UL interference or DL pilot pollution

15 © 2005 Nokia


Compare CHT and VIBO call drop situation

VIBOCHT

T313: 3 s

N313: 20 (200 ms)

T313: 5 s

N313: 50 (500 ms)

Around 3.2 s Around 5.5 s

T313 was changed from 3 to 8s UE can wait more time to keep radio link

16 © 2005 Nokia


T313 N313 N315 T315 PS Call

17 © 2005 Nokia


Parameter Setting (T302, N302, T313, N313, N315, T315)

18 © 2005 Nokia


Dropped RABs – RAB_ACT_FAIL_PS_BACK_RADIO

N313 =50 “out of sync”indicators

Timer T313=8s started

Timer T313 expires

Radio Link Failure

Re-establishment timer T315 started

When the criteria for radio link failure are fulfilled.The timer is started only if radio bearer(s) that are associated with T315 exist. NRT radio bearers are associated with T315

Cell Reselection

Timer T_RLFAILURE started Timer T_RLFAILURE expires=2s

RNC receives NBAP:RADIO LINK

FAILURE –message form BTS with a

cause value "Synchronization

Failure"

T_L1_Sync_ReEstab_Wait –timer started in RNC = 2s

T_L1_Sync_ReEstab_Wait –timer expired

T315 value is checked

RRC_ConnRe-estabTmr -timer started : T315 + (T302*N302) = 30 + ( 4*7 ) = 58s

no RRC:CELL UPDATE message is received from the UE -> the Iu release request with a cause value ‘Radio Connection With UE Lost’ is sent to the PS-CN

RRC_ConnRe-estabTmr –timer expired

NRT

If T315 = 0, then all NRT radio bearers are released locally and the

Iu release request with a cause value ‘Radio Connection With UE

Lost’ is sent to the PS CN(s)

If T315 > 0, the waiting of RRC connection re-

establishment is initiated

RRC: CELL UPDATE received

NRT

N_OUTSYNC_IND “out of sync” indicators = 8

Next

slide

Next

slide

T315 expiredT302 running => continue to wait response to cell update, according to T302

Wei Yun

Note

N313 - no. of out of sync indicators T313 - after N313 achieved, time to wait before declare RL failure (only RL release but Iu still remain) when UE receive BLER > 20% => out of sync N315 - no. of in sync indicators after T313 started, after achieved N315, T313 stopped T315 - time to wait for cell update after RL failure (after T313 expired) (after this timer expired, UE will go back to wait for paging in idle mode)

19 © 2005 Nokia


Dropped RABs – RAB_ACT_FAIL_PS_BACKG_RADIORNC

NBAPRNC RRM

BTS NBAPUE

UE loses radio connection

Suitable UTRAN cell can be selected within T315 => UE moves to CELL_FACH state

MS is in CELL_DCH state

capacity_req

NBAP:RADIO LINK FAILURE

capacity_allocation

NBAP_rl_failure

RRC:CELL UPDATE rrc_cell_update_req

RRC:MEASUREMENT CONTROL

State transition from CELL_FACH to CELL_DCH state executed

rl_fail_ind

NBAP_rl_rel_req

Radio Link DeletionNBAP_rl_rel_resp

RNC RRC-c

[Cause: Radio Link Failure]

Loss of L1 sync. detected timer

T_RL_Failureexpires

Timer RRC_ConnRe-estabTmr expires

RRC:CELL UPDATE CONFIRM[New C-RNTI]RRC:UTRAN MOBILITY INFORMATION CONFIRM

Capacity request received from the UE or MAC-c entity

T315>0 => UE initiates a cell selection procedure and starts re-estab. Timer (T315) T315>0 => RNC initiates a release of the (dedicated

radio resources and starts a Re-establishment timer: T315 + (T302*N302) = 30+(4*7) = 58s

[Traffic Volume Measurements]

branch_deletion_req

If more than one RL, the HC is informed for the RL failure

RNC RRC

Traffic Volume Measurements is sent

UE is in CELL_FACH state

UE is in CELL_DCH state

Cell update received from UE before the re-establishment timer expires

Wei Yun

Note

N302 & T302 - similar to N300 & T300, the different is N300 & T300 for RRC Conn Req but N302 & T302 for Cell Update

20 © 2005 Nokia


T315=0 – PS Transaction lost due to radio failure (out-of-sync)(Global)

Network View

T_RLFAILURE = T_L1_sync_re_estab = 2s

T_L1_Sync_ReEstab_Wait = 2 s expire

21 © 2005 Nokia


T315=10 sec – PS Transaction lost due to radio failure (no Cell Update received within T_rrc_conn_re_estab)(Global)

T_rrc_conn_re_estab = T315 + (N302 * T302) = 10 + (7 * 2) sec = 24 sec

Network View


22 © 2005 Nokia


T315=10 sec PS Transaction lost due to radio failure

• PS Call dropped due to radio failure

• T315 expires in UE

• PS transaction re-established by PS Core Paging

• UE will then answer by RRC_Connection_Request with cause “termination background call”

UE View (Global)

Note: Timestamps not aligned with RNC System time

23 © 2005 Nokia


T315=10 sec – PS Transaction re-established after radio failureCell Update (RLF) received before T_rrc_conn_re_estab expiry (Global)

Cell_Update received before T_rrc_conn_re_estab (=24 sec) expiry

Cell Update (radiolinkFailure)

Network View


24 © 2005 Nokia


T315=10 sec PS Transaction re-established after radio failure

• similar scenario than previous slide

• Cell Update retrieves data call

UE View (Global)

Note: Timestamps not aligned with RNC System time

25 © 2005 Nokia


Test Result

26 © 2005 Nokia


T313 test Result in NetworkNetwork BaseNetwork Base

27 © 2005 Nokia


T315 Tuning resultRNC BaseRNC Base

Timing Parameter v2

Documents

fach rrc

rrc connection establishment

rrc connection requestsnbap

rrc connection setupnbap

startedrach rrc

ongoing rrc procedure5

rnc initiates rrc procedure

radio link setup request