top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

LTE: Will UE reads PSS and SSS signals once handover command received from from source eNB ?

+1 vote
1,137 views

Once UE receives mobility control (contatins pci and dl BW etc) info in rrcconnectionreconfiguration message from source eNB, will UE reads PSS and SSS of target eNB ? bcz already have given pci .

posted Jul 31, 2014 by Bheemappa G

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

3 Answers

+1 vote

As per my understanding, UE shall perform PSS and SSS at target cell otherwise how would it be able to latch on correct/intended cell. After reading PSS and SSS, UE knows the PCI of cell.

answer Jul 31, 2014 by Vimal Kumar Mishra
thanks Vimal Kumar Mishra  .

yes but in mobility control info contains PCI  ..
Even I have mentioned in my answer, first UE shall do PSS and SSS then only it can find out the correct destination (target cell). At a particular time or location, UE may see # number of cells and but objective is to latch on correct destination (i.e. target PCI within the mobility control info).
Yes i agree ...ok let me explain still more ... currently I am doing intra frequency handover ,once ue receives reconfiguration message contains mobility control info ,UE  started sync with target eNB (continues RACH is happening but not received target eNB) but from UE log i came to know that UE is not reading PSS and SSS signals . so i think UE is facing UL sync issue .... ie. current SFN  present in UE side is different and    target eNB current SFN is different. And one more thing observed from UE logs is CRC failure while PBCH decoding .
please suggest where i am going wrong..

UE log :
0 votes

I think UE reads PSS and SSS not only to get the PCI value but also reads the PSS and SSS to get sync at radio frame, sub frame and symbol level to the target cell. After sync with target cell UE will be able to trigger the RACH procedure at the correct radio/sub frame/symbol. If RACH is successful then UE sends rrcreconfiguration complete message to the target cell to inform successful HO.

answer Oct 12, 2014 by Veer Pal Singh Yadav
0 votes

Hi Bheemappa,

DId you find the reason for your problem back then. I face a similar issue, could you please help?

Thanks

answer Nov 10, 2016 by Ankit Khandelwal
This is a very old thread, may be ask a fresh question and people may be able to help you.
Similar Questions
+2 votes

I have basic handover related query. How source eNodeB get to know when it has to trigger handover required message ? I mean to ask, how a source eNodeB come to know the threshold values of RSRP or RSRQ or both (related to target eNodeB) , required to do a successful handover towards eNodeB ? Is it due to network planning ?

+1 vote

Can you, please explain what happens for the common channels? The PSS/SSS and PBCH have a fix position in time-frequency domain so in the area between the sectors we will have those REs (resource elements) and RBs (resource block) that are allocated to them that will interfere.
Also, can you explain how it is possible to decode the signals when the UE measures a negative SINR?

...