dr is query regding the RLT counter(radio link timeout) for me??
does the RLT counter comes into picture in SDCCH phase also..i am raising this query coz the SACCH frame in SDCCH phase is 470.2 ms and the avg holding time of SDCCH will be in some 2 to 4 seconds and generally RLT is kept @ 20..i.e 20*470.2 ms which is well above the avg holding time of SDCCH??
yes : the RLT works for SDCCH as well as for TCH. And it works in the same way, with the same RLT value = 20.
You said tht SDCCH phase lasts only 4s. I agree. But if the radio link is poor, then the phase will last much longer. For ex. the MSC sends the AUTH REQ to the MS. If the MS does not receive this message due to poor radio conditions, then the MSC will retransmit it. Therefore, the duration increases.
At the same time, the MS will decrease the S counter if the SACCH is not received.
What I’m trying to say is that the SDCCH phase is “stalled” when the radio is bad. The S counter has plenty of time to reach “zero”.
well..thnx pix..dt tells the whole story..actually wt hpnd is in my network is we increased the RLT to 28 frames and the SD drop improved drastically(by 0.25%) and a lil improvement in TCH also..and was wondering hw ds cud happen..drilled down to lot of calculations(d one I referred above) and wasnt convincd enuf coz d calculations above doent allow so..