Handover failure Reason using TEMS

[adewijaya]

your picture is OK, we can seeing clearly. Your question already answer well, isn't it?

[theumar@hotmail.com]

HO Command send by BSC with information of target channel after Channel Preparation in Target Cell. In this case HO CMD sent but HO Failed because MS was not able Access Target Channel, it could be because of Interference at target channel or poor UL condition of target cell

[Areej]

HO Command send by BSC with information of target channel after Channel Preparation in Target Cell. In this case HO CMD sent but HO Failed because MS was not able Access Target Channel, it could be because of Interference at target channel or poor UL condition of target cell

but congestion can't be an option after the command is sent right ??

[adewijaya]

HO Command send by BSC with information of target channel after Channel Preparation in Target Cell. In this case HO CMD sent but HO Failed because MS was not able Access Target Channel, it could be because of Interference at target channel or poor UL condition of target cell

Question is : capacity could be became reason to rejection HO or Not? just that and i said : it could be aside due to Interference absolutely

[Areej]

Question is : capacity could be became reason to rejection HO or Not? just that and i said : it could be aside due to Interference absolutely

Capacity ofcourse one of the reasons of HO failure, but the question here , if the MS got 'handover command message' - which means that a traffic channel is already found - and the handover failed , I can't think of the congestion as a reason ??

[adewijaya]

not directly affected, on statistic separated two kind : Block or Fail, so HO fail isn't related to Congestion but HO block it could be due to no channel

[leelio]

you can try to check which cell was chosen to be handed over a call, & does that cell experience congestion in that period? (you can see this cell during handover command)

sometimes delay in handover happen and may cause wrong interpretation.

[Areej]

you can try to check which cell was chosen to be handed over a call, & does that cell experience congestion in that period? (you can see this cell during handover command)

sometimes delay in handover happen and may cause wrong interpretation.

the problem is that I don't have access to check the congestion on the cell
I only can use the events and layer 3 messages and TEMS windows to investigate

thanks anyway

[salmeterol]

When a telephone gets a "handover command", that means a radio source allocated for this phone on target cell. TCH Congestion is not a HOF reason.

This allocated source is a TCH Channel, not a SD Channel.

SD CONGESTION MAY OCCUR AFTER HO DECISION !!!!

You cannot understand congestion status with TEMS. If you cannot get daily KPI values of target cell; then just take short call tests around it. If you make a Half Rate call; that means cell has high traffic and is closing to TCH Congestion. Means so many AMR HR-FR handovers happening in target cell => may cause SD Congestion.

Don't forget to check ping-pong handovers too...
Intensive handover traffics load SD channels.

Don't forget; there should be open sd channels for finishing handovers.
But these are rare exception situations.

You can check dl interference & dl quality problems too. Probably interference happened on target cell. Or target cell may be overshooting with bad quality signal.

Just go and take a test on roads between source & target cells and look for some problems.......

:-)

[fdanaei]

Hi, I think friends said main reasons for handover failure. But dont forget to check same BCCH+BSIC Problem. also existence of faulty TRX in Target Cell.