[Aakriti]

Hi Pix,How are you. I want to know about a Handover Parameter in ALU B-10 i.e NB_PREF_CELLS,It says Maximum number of candidate cells sent in one HANDOVER
REQUIRED.Default value =3,
But if we see Other vendors generally the Default value =6.
So what are your suggestion on this, Changing the Value from 3 to 6 will it Improve HOSR & TCH Drop..
Please suggest

[pix]

hi,

it’s just the number of candidate cells which are sent to the target MSC when the serving BSC detects a HO to an external cell.

The HO CMD message may contain several candidate cells. The MSC will attempt to get a TCH on the 1st cell of the list. If the first cell is congested, then it will try with the second one, and so on.
By putting only 1 candidate cell in the message, you might delay the HO, if the target cell is congested : the BSC would have to wait for the reject from MSC, and then propose the second cell. That is a loss of time.
Proposing 6 cells at once is quite bad because if the 5th best candidates are congested, then the MSC will test the 6th candidate, which might probably a terrible candidate. If the 6th has a TCH “free” then the MS will have to go there. That might be dangerous.

As you understand, this parameter is useful only if the external target cells are congested !

Usually, 2 or 3 cells is plenty enough. If none of them is available, then you might as well jeep the MS in the current serving cell.

If the external cells are located in a dense area (multiband cells, microcells, etc), then choosing 6 candidates looks “less” dangerous.

[Aakriti]

Hi Pix,

Thanks for the info,But anywhere in B-10 documentation it is not shared that this parameter is only for cells when HO is detected to an external cells.

Can you let me know which Doc you are refering,As i searched everywhere for this Parameter,But unable to find any discreption.

[pix]

aakriti,
check out the HO MANAGEMENT document 🙂

Only if HO is external, then the HO REQ is sent to MSC. If HO is internal, then there is no HO REQ, only an “internal” HO CMD to the target cell, without any intermediate.

I know you will only trust the doc, so have a good read 🙂

Cheers
pix

[Aakriti]

No Pix, Please don’t think that way…I am absolutely sorry if you are feeling Bad, Actually i asked for a doc so that i can know some Good ALU doc Other than B10 Dictionary, Since there are so many parameters to play with in ALU system, But the B10 Doc has Only Default values, No Proper Discreption & No recommendations,Impact on KPI’s.

My Only intention was to know if there are some good Doc’s…

Sorry for making you upset

[pix]

i’m not upset at all, don’t worry. I just assumed you were like me : I trust only the documents, and someone can spend hours explaining something to me, but I will still have to read the doc…

Trust no one…

So the document name is : Handover Management.

It’s not a joke 🙂

Cheers !
PIX

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