RLT in 3g?

[s.sunilpal123]

Dear friends & experts...

I have a question. What is the 3G counterpart to the process of Radio Link Timeout in GSM? Please explain in detail because this concept is new to me...

Thanks in advance!

[adewijaya]

Dear friends & experts...

I have a question. What is the 3G counterpart to the process of Radio Link Timeout in GSM? Please explain in detail because this concept is new to me...

Thanks in advance!

see this link : http://www.finetopix.com/huawei/18594-prach-propagation-delay.html

[jan74]

see this link : http://www.finetopix.com/huawei/18594-prach-propagation-delay.html

I think he is wondering about RadioLink Timeout and not Timing Advance? RLT in 3G is something you can set as in GSM. The timer involved is T313 and its set to 3s in cases I have seen. However, there is a great feature called RRC-Reestablishment which allows your handset to setup the call again after it has regained synchronisation. If you are looking at changing your RLT to improve the DCR, it might be worth looking at the Re-establishment feature as it is a better solution.

[s.sunilpal123]

jan74, could u please explain in detail the timer T313 and how it functions during an actual call? Also what is the normal setting range of this timer? (In GSM, RLT takes values 4 to 64, right, in steps of 4? What about T313?) Also in GSM RLT was linked with SACCH, what channel is there in 3G for this?

[adewijaya]

When the T313 timer expires, the UE declares radio link failure. After
Qout is detected, the UE Power Amplifier (PA) is turned off. Because the Downlink cannot
be demodulated reliably, power control information is not received; thus the PA is turned
off to avoid generating interference on the Uplink. If the Qout condition is maintained for
N313 frames, the UE declares CPHY-out-of-sync. The UE then starts a process similar
to initial acquisition of the radio link, because the system timing is considered lost at this
point. If the acquisition process does not succeed within T313, the link is considered lost
and radio link failure is declared.
The N313 and T313 parameters directly in.uence how long a call can be maintained
in bad RF conditions. If these parameters are too short, many calls may be prematurely
dropped under rapidly changing RF conditions. On the other hand, setting these times
too long allows more time for calls to recover but may affect call quality and resource
utilization
When the T313 timer expires, the UE declares radio link failure. After
Qout is detected, the UE Power Amplifier (PA) is turned off. Because the Downlink cannot
be demodulated reliably, power control information is not received; thus the PA is turned
off to avoid generating interference on the Uplink. If the Qout condition is maintained for
N313 frames, the UE declares CPHY-out-of-sync. The UE then starts a process similar
to initial acquisition of the radio link, because the system timing is considered lost at this
point. If the acquisition process does not succeed within T313, the link is considered lost
and radio link failure is declared.
The N313 and T313 parameters directly influence how long a call can be maintained
in bad RF conditions. If these parameters are too short, many calls may be prematurely
dropped under rapidly changing RF conditions. On the other hand, setting these times
too long allows more time for calls to recover but may affect call quality and resource
utilization.

[adewijaya]

Here is some detail describe with T 313 and N 313

[sonerss]

Hi adewijaya

can you convert this pic. to *.zip file.. ?

Thanks


Here is some detail describe with T 313 and N 313

[zeezzoo]

dear,
the best way to learn is to read by your own .
this is E******* Radio network functionality : WCDMA Radio Network Functionality.pdf - 4shared.com - document sharing - download (http://www.4shared.com/document/Q1DT4eyl/WCDMA_Radio_Network_Functional.htm)

Read the 3rd chapter " Radio Connection Supervision " it will be very useful . it's also samll ,about 20 pages .

[Alphab]

anybody could advice on how to change the T313 value from default 3 sec in E******* as i know hard-coded to a value lets say 4 sec ...

As i check from SIB1 one operator with E******* vendor has such value of 4 sec in T313 setting ...

Any feedback would highly be appreciated ... Thanks in advance

[rjcell]

I think the parameter is TRLFailure

Meaning: Radio Link Failure Timer Duration. When the radio link set is in the synchronized state, the NodeB starts the timer after it receives successive out-of-sync indications of the number defined by NOutsyncInd. The NodeB shall stop and reset the timer after receiving successive in-sync indications of the number defined by NInsyncInd. When the timer expires, the NodeB triggers the radio link failure process, and indicates which radio link set is out-of-sync.
GUI Value Range: 0~255
Actual Value Range: 0~25.5, step: 0.1
Unit: s
Default Value: 50
Recommended Value: 50

[rnpopt]

Hi rjcell,
I think TRIFailure is for UL RLT (it starts when the 'Node B' gets succeessive out of sync) and T313 is for DL RLT (it starts when the 'UE' gets successive out of sync).


I think the parameter is TRLFailure

Meaning: Radio Link Failure Timer Duration. When the radio link set is in the synchronized state, the NodeB starts the timer after it receives successive out-of-sync indications of the number defined by NOutsyncInd. The NodeB shall stop and reset the timer after receiving successive in-sync indications of the number defined by NInsyncInd. When the timer expires, the NodeB triggers the radio link failure process, and indicates which radio link set is out-of-sync.
GUI Value Range: 0~255
Actual Value Range: 0~25.5, step: 0.1
Unit: s
Default Value: 50
Recommended Value: 50