Tuesday, 22 July 2014

LTE Timers

Timer
Start
Stop
At Expiry
Recommended Value
T300
This timer is started when the UE sends
RRCConnectionRequest.
Reception of RRCConnectionSetup or RRCConnectionReject
message, cell re-selection and upon abortion of connection
establishment by upper layers
the UE directly enters the RRC_IDLE state
200ms
T301
This timer is started when the UE sends an RRC Connection Reestablishment Request message
The timer is stopped if the UE receives an RRC Connection
Reestablishment or RRC Connection Reestablishment Reject message. The timer is also stopped if the selected cell becomes an unsuitable cell.
the UE enters the RRC_IDLE mode.
200ms
T302
Reception of RRCConnectionReject while performing RRC connection establishment
This timer is stopped when the UE enters the RRC_CONNECTED
mode or performs cell reselection
Informs upper Layers
4s
T303
Starts when access is barred while performing RRC CONNECTION ESTABLISHMENT for MO(Mobile Originating) calls
Upon entering RRC_CONNECTED and upon cell re-selection
Informs upper Layers

T304
Starts at the Receipt of RRC CONNECTION
RECONFIGURATION message along with Mobility Control Info OR at the receipt of mobility from EUTRA command
message including CELL CHANGE ORDER
Criterion for successful completion of handover to EUTRA or cell Change order is met (the criterion is specifiedin the target RAT incase of inter-RAT)
In case of cell change order from E-UTRA or intra
E-UTRA handover,initiate theRRCconnectionreestablishment
procedure; Incase of handover toEUTRA,
perform the actions defined in
thespecificationsapplicable forthe source RAT
For EUTRAN: 500ms for
GERAN: 8000ms
T305
Access barred while performing RRCconnectionestablishment for mobile originating signalling
Upon entering RRC_CONNECTEDand upon cell re-selection
Informs upper Layers

T310
Upon detecting physical layer problemsi.e. upon receiving
N310 consecutiveout-of-sync indications from lowerlayers
Upon receiving N311 consecutive in-sync indications from lower
layers,upon triggering the handover procedure and upon initiating
the connection re-establishment procedure
the UE enters the RRC_IDLE mode if the security
mode is not activated. If the security mode is
activated, the UE initiates an RRC connection
reestablishment procedure.
1000ms
T311
Upon initiating the RRC connection re-establishment
procedure
the UE selects an E-UTRAN or inter-RAT cell to camp on.
the UE enters the RRC_IDLE mode
1000ms
T320
Upon receiving t320 or upon cell (re)selection to E-UTRA
from another RAT with validity time configured for
dedicated priorities (in which case the remaining validity
time is applied)
Upon entering RRC_CONNECTED,when PLMN selection is
performed on request by NAS, or upon cell (re)selection to another
RAT (in which case the timer is carried on to the other RAT)
Discard the cell reselection priority information
provided by dedicated signaling

T321
starts upon receipt of measConfig including a
reportConfig with the purpose set to reportCGI
Stops at either of following cases:
1. Upon acquiring the information needed to set all fields of
Global CellId for the requested cell
2. upon receipt of measConfig that includes removal of the
reportConfig with the purpose set to reportCGI
At expiry initiates the measurement reporting
procedure, stop performing the related
measurements and remove the corresponding
measID

No comments:

Post a Comment