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RF engineer
2009-03-20, 01:36 AM
Dear
Some one can help with the reason of difference BCCH rxlevel in layer 3 and neighbor window in tems as i checked the difference is around 10dB and it still can not make HO to the next neighbor which it has better rx level

nupong
2009-03-20, 02:07 AM
I can't see the attached file as my poor rep (:P) however, have u checked whether the HO margin between those cells is correct?

RF engineer
2009-03-20, 02:45 AM
Dear
thanks for your help to explain for in the layer 3 when i checked the index for BCCH for serving cell it show that MS read around -70dBm and in the neighbor window it show -80dBm we are using SFH so i think power control not effect and the second neighbor has Rx level greater than server by 20db

venom
2009-03-20, 02:49 AM
Dear
Some one can help with the reason of difference BCCH rxlevel in layer 3 and neighbor window in tems as i checked the difference is around 10dB and it still can not make HO to the next neighbor which it has better rx level

In layer 3 the report is of not serving cell, it is of neighbor cell. The signals shown in Layer3 is of IDLE NEIGHBOR, not SERVING CELL, whereas in the other window u r served by that neighbor, there could be a milisecond difference bruv.

In second window, always the first element is the serving cell, so please don't mix it with the neighbor list shown in Layer3 :)

MINTO
2009-03-20, 02:54 PM
In layer 3 the report is of not serving cell, it is of neighbor cell. The signals shown in Layer3 is of IDLE NEIGHBOR, not SERVING CELL, whereas in the other window u r served by that neighbor, there could be a milisecond difference bruv.

In second window, always the first element is the serving cell, so please don't mix it with the neighbor list shown in Layer3 :)..

also in layer 3 message it shows rxlevel srving cell..you can calculate it as(Rxlevelminacess-recived level)like(102-80=42) in layer 3 it is always +ve

RF engineer
2009-03-20, 07:04 PM
dear lccengr
you can also see the Rx level for the both serving and neighbor cell
BR
aso

MINTO
2009-03-20, 08:14 PM
dear lccengr
you can also see the Rx level for the both serving and neighbor cell
BR
aso
in layer 3 message it shows rxlevel srving cell..you can calculate it as(Rxlevelminacess-recived level)like(102-80=42) in layer 3 it is always +ve
thats why both values come different

http://www.finetopix.com/images/misc/progress.gif

davidbrayan
2009-03-21, 01:02 AM
yes, you can see serving cell as well but the parameters you highlighted were incorrect. lccengr said it right, based on the diagram you showed.
now verify the details with the image attached.
and consider arvind also when comparing Rxlevels , in L3 they are in GSM format(0 to 63, where 0 is minimum and 63 is maximum signal strength) while in other window they are in dBm(-ve values).
RED color blocks are for serving cell params, BLUE blocks for Neighbors.
BR
db



dear lccengr
you can also see the Rx level for the both serving and neighbor cell
BR
aso

sataron
2009-03-21, 01:27 AM
Dear
Some one can help with the reason of difference BCCH rxlevel in layer 3 and neighbor window in tems as i checked the difference is around 10dB and it still can not make HO to the next neighbor which it has better rx level
If U use E/// HW - check LAYER and LAYERTHR parameters on booth cells - maybe in one of it u found wrong values :p

raedsab
2009-03-21, 02:18 AM
Dear RF engineer,
what is the time advance value?



Dear
Some one can help with the reason of difference BCCH rxlevel in layer 3 and neighbor window in tems as i checked the difference is around 10dB and it still can not make HO to the next neighbor which it has better rx level

hassen
2009-03-21, 07:52 AM
Dear
Some one can help with the reason of difference BCCH rxlevel in layer 3 and neighbor window in tems as i checked the difference is around 10dB and it still can not make HO to the next neighbor which it has better rx level
due to gsm specification

Value range
-110 to -47

I mean -110 - (-49) =-61
for BCCH no power control

Rx full serving cell =30
-110 + 30 = -80 dbm

br hassen

venom
2009-03-21, 01:39 PM
dear lccengr
you can also see the Rx level for the both serving and neighbor cell
BR
aso


I know bruv, i can see everything in ur snapshot... but the snapshot which u have attached for this question is having 2 information, neighbors and serving both. You are mismatching the same cell id in two different places.

Remember:
Whether you are in dedicated mode or idle mode, your NEIGHBOURs will remain idle. So supposing that you are doing a dedicated mode call test, you are still receiving the idle mode signals of your neighbors !!!

In Layer3 snapshot, your rxlev of first neighbor is good enough to be served that is why in your 2nd window it was served by that neighbor. The difference of moving from 1st neighbour to served cell is really quck. Check for the handover message reported in TEMs !

David has shown you the nice picture, pls review it, i hope it answers your question now !

RF engineer
2009-03-22, 09:18 AM
dear
TA for serving cell is 1

timedomain
2009-04-03, 12:47 AM
Neighbor window is using values directly from layer3 messages, there is no other source for that window, so this difference is because of "like(110-80=40)". if you check the values in neighbour window changes by every new measurment report, when ms gets new measurment report, tems is updating that window

RF engineer
2009-04-03, 12:45 PM
dear timedomain
Thanks for your explanation
BR

elche
2009-04-27, 12:51 PM
You should also check if you have defined all the neighbors' ARFCN in MBCCHNO parameter.

kahnoie
2009-06-13, 05:31 PM
The RXLEV values must be typically between -98 to -106 dBm.
The HO would depend on HANDOVER MARGIN (must be atleast -24 DB)

Regards,
Amit
agarwalamit081@gmail.com

nevy_14
2010-06-28, 05:30 PM
the neighbour RxLev in Layer 3 is using "index"...
the value range is between 0 - 63.
0 = -110 dBm
1 = -109 dBm
.
.
.
63 = -47 dBm

a slight difference in your neighbour level ( -61 dBm in neighbour window) perhaps due to power control. but your serving cell pointing the correct value ( 30 in layer 3 then -80 dBm in neighbour window).
The Example from hassen should clear things up..

BR,
nevy_14

Processor
2010-06-28, 07:05 PM
Very good info from nevy_14 and hassan of course...sincerely i neva knew this 'Index' thingy.