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justdream
2009-04-23, 08:33 AM
Guys, les amis

I noticed during one of my drive tests that I get handover failure but the call didn’t drop…..how come we got handover failure and the call didn’t drop?

Please explain to me as I’m newbie in optimization
Thanks a lot :hug:

kokoeg
2009-04-23, 09:17 AM
Guys, les amis

I noticed during one of my drive tests that I get handover failure but the call didn’t drop…..how come we got handover failure and the call didn’t drop?

Please explain to me as I’m newbie in optimization
Thanks a lot :hug:

there is difference between call drop and HO failure if you got HO failure mobile will try to return to last serving cell if it can see good level from it.

As I think

jamonpa
2009-04-23, 12:04 PM
a ho fail is a event to say in the network has a problem in a adj defition or simply the target cell no have resource to allow the HO. But the continuos HO fail can be generate a Drop when the call are dragged.

A drop call maybe is a effect to the continuos HO fail, buto HO fail no ever end in a Drop call

justdream
2009-05-23, 09:19 PM
what about the Neighbour list????
I need some strategy for Neighbour list please :hug:

blast
2009-05-24, 04:00 AM
try to read this :[Only registered and activated users can see links] ([Only registered and activated users can see links])

maybe can answer your question....:D

venom
2009-05-24, 04:40 AM
Guys, les amis

I noticed during one of my drive tests that I get handover failure but the call didn’t drop…..how come we got handover failure and the call didn’t drop?

Please explain to me as I’m newbie in optimization
Thanks a lot :hug:

I would recommend you to learn MOC and MTC Procedures, Handover Procedures, Location Update Procedure, IMSI/TMSI Assignments etc!!

Handover Failures doesn't mean the call drop !! They both are different things with different timers and counters !! Both are having different reasons to occur !! Once you know the basics then you would probably find the difference between the two, cheers

justdream
2009-06-13, 01:32 AM
Friends, How can I use TEMS to show me (the target cell name, BCCH, CID.....any information) in case of handover failure ?

To know which cell I use trying to handver then it failed
Thanks a lot

triple-x
2009-06-13, 02:53 AM
Friends, How can I use TEMS to show me (the target cell name, BCCH, CID.....any information) in case of handover failure ?

To know which cell I use trying to handver then it failed
Thanks a lot

I'd suggest you to see the big picture by comparing your drive test result (the HO failures) and the cell-to-cell HO statistic, because sometimes what you find from drive test doesn't necessarily a real problem and you'll end up wasting your time in investigating something that's insignificant.

justdream
2009-06-13, 03:54 AM
Thanks Triple-x but this handover failure leds to call drop, so I wan tto know which cell the mobile tried to hand to it (using TEMS)

guess.who
2009-06-13, 05:14 AM
see the measurement reports in layer3 just before the ho failure.....it will help u answer ur query....

triple-x
2009-06-13, 06:36 AM
Thanks Triple-x but this handover failure leds to call drop, so I wan tto know which cell the mobile tried to hand to it (using TEMS)

What I was trying to say is, not to be focused on only drive test but look also the cell statistic from the BSC. I saw many organizations don't really know how to judge the network quality, they do a lot of drive tests, putting so much effort on it but neglecting the importance of the statistic. Bear in mind that most of the customers don't do the same with what you're doing in drive test, going here and there, turning left-right etc. most of the customers are in stationary position and this is the main contributors of your network.

Nemer
2009-06-27, 01:19 AM
IF you use Tems,
Look under messages reports in layer3 > Events > Ctrl+F (faind events).
So it is possible to search for any event.

ghassen
2009-06-27, 01:30 AM
Guys, les amis

I noticed during one of my drive tests that I get handover failure but the call didn’t drop…..how come we got handover failure and the call didn’t drop?

Please explain to me as I’m newbie in optimization
Thanks a lot :hug:

this is what we call HO faillure with reversion to old channel

hassen
2009-06-27, 02:51 AM
hi
I guess so there are neighbours with the same bsic bcch ,the mean raison to have Ho failure ,i mean when ms try to make Ho to target cell ,this target cell is not the same cell that mobile sent measurement report about it to bsc ,and bsc can't know wich cell ,it use as reference bcch and bsic,so bsc send to ms wrong setting.

br hassen

ghassen
2009-06-27, 02:53 AM
hi
I guess so there are neighbours with the same bsic bcch ,the mean raison to have Ho failure ,i mean when ms try to make Ho to target cell ,this target cell is not the same cell that mobile sent measurement report about it to bsc ,and bsc can't know wich cell ,it use as reference bcch and bsic,so bsc send to ms wrong setting.

br hassen

this will not result in old channel reversion but only to HO fail and call drop

hassen
2009-06-27, 03:09 AM
this will not result in old channel reversion but only to HO fail and call drop
ok

call drop due to what!

br hassen

Gustavo9985
2009-06-27, 03:46 AM
Because there was many server and although you had handover failure the handover did it at other cell.

electron
2009-06-27, 05:42 AM
One reason of HO fail is feeder cross connection When you are into main lobe of antenna pattern you will see HO fail

Another reason is the neighbor cell that MS going to hand over to that has TCH congestion

I suggest to you find the reason of HO fail during your DT.I mean,why MS wants to make HO?(what is the reason of HO decision?)


BR
Reza

hassen
2009-06-27, 06:14 AM
One reason of HO fail is feeder cross connection When you are into main lobe of antenna pattern you will see HO fail

Another reason is the neighbor cell that MS going to hand over to that has TCH congestion

I suggest to you find the reason of HO fail during your DT.I mean,why MS wants to make HO?(what is the reason of HO decision?)


BR
Reza
hi my friend

i am agree with you about cross feeder that can cause ho fail but about the raison tch cong i am not sure because after ho decision bsc has assigned a tch to Ms.

br hassen

kais
2009-06-27, 06:12 PM
u should différenciate between :


- HO Fail préparation phase (before tch assignement)
- HO Fail execution phase

thiepvt
2009-06-27, 07:18 PM
Pls anyone help me, can anyone explain for me about used "Counter" for analysis network parameter such as Neighbour,HO,....:L:L..Thanks

hassen
2009-06-27, 08:01 PM
u should différenciate between :


- HO Fail préparation phase (before tch assignement)
- HO Fail execution phase
hi
i think before it called ho lost following by drop call due to low signal as example.

br hassen

RF engineer
2009-06-27, 08:15 PM
if you want to know exactly you handover failure reason with specific reason you can check in HO stat reasons( DL/UL level,DL/UL Quality.PBGT,,,,,,) and there can be decided what is the

electron
2009-06-27, 10:46 PM
hi my friend

i am agree with you about cross feeder that can cause ho fail but about the raison tch cong i am not sure because after ho decision bsc has assigned a tch to Ms.

br hassen

Dear Hassen,


As you know in GSM technology we have kind of HO that named Hard hand over.According to this kind of HO at first BSC release TCH from serving cell and then assigned to target cell.Some time target cell has not idle TCH therefor BSC will assign MS to last serving cell.Now we suppose that target cell has not idle TCH and we will come back to serving cell it will cause some time HO fail and retry HO and call drop i think every thing is clear now...


Regards
Reza

hassen
2009-06-28, 02:03 AM
Dear Hassen,


As you know in GSM technology we have kind of HO that named Hard hand over.According to this kind of HO at first BSC release TCH from serving cell and then assigned to target cell.Some time target cell has not idle TCH therefor BSC will assign MS to last serving cell.Now we suppose that target cell has not idle TCH and we will come back to serving cell it will cause some time HO fail and retry HO and call drop i think every thing is clear now...


Regards
Reza
Hi reza

from signaling A interface about Ho
as you know before bsc release tch from serving cell it should receive ho complete from target cell.
please see attached file GSM Handover Call Flow

br hassen

thawrani75
2010-05-24, 10:38 PM
If one Ms is moving from one cell to another cell , but another cell has blocking/congestion, Can handover is completed and not?
Pls clear me about it.
all condition are good for this handover-------.
1> no h/w issue on serving and neighbur cell.
2. handover is define bothway with this cell.
3. no h/w issue.


I hope , this handover is not completed, but this number is VIP, then wht handover is completed ?

pls clear me about this?

takeiteasy612
2011-07-08, 11:01 PM
HI guys
Please check the link download, may be it is broken

Junio
2011-08-03, 12:35 AM
there is difference between call drop and HO failure if you got HO failure mobile will try to return to last serving cell if it can see good level from it.

As I think
Hi all I try to analysis the Inter-RAT fail and to propose the solutions for to resolve it but it's not easy for me because i have not enough document . can you recommended me the good doc .

Thank a lot .