Maximum no. of SDCCHs

[haider79]

Dear Experts,

Please i need your support to know the maximum number of SDCCHs could be defined per TRX in E///, appreciate if any one can share document for that.

Many thanks
haider79

[Ahmed.]

Dear Haider,
I do not have a document but you can judge like this:

One can define 25% of the TRX capacity of a channel group. In E*******, there is a parameter called MAXNOOFSDCCH which has to be toggled allowing one to define more than 25% of the TRX capacity.

[Ahmed.]

An example is about a cell with 4 TRXs.

1 BCCH TRX, 3 TCH TRX

We could define max 6 SDCCHs (2 from the BCCH and the 6 in the TCH TRXs). 8 were max, it is 25 % of the total capacity of these 4 TRXs.

Can you post you cell configurations?

[justdream]

is it preferred to define all Static SDs in one TRX or distribute between TRXs or no difference at all?

[Ahmed.]

Well, it depends on the band. Go for those which are interference free. The BCCH is clean usually, so I have always preferred the SDCCHs on that. SDCCH can also be put on hopping, & I have heard of claims that it brings improvement. I have seen degradation when I tried the same.

[ashraferto]

Its depend on the SD traffic offered on that cell which depend on the cell location (Lac boarder, downtown, etc...) so finally you judge how many SD required in each cell independently on the TRX number.

[Muhammad Imran Rafique]

Dear All,

Please note E// allows,
1) SD can be configured purely based on defined TRX. (First limitation)
2) BSC Exchange property MAXNOOFSDCCH allows you to define 2,3,4 SD per TRX, still you cannot cross point 1. It is still your limiting factor (# of TRX configured)
3) (# of TRX configured) can only be crossed if you have additional feature INCREASEDSDCAP, Then you can have double the SDCCH channel w.r.t (# of TRX configured)
If anyone have anyother querey, i.e OL & UL scenarios etc dont hesitate, let me know.

BR//
Imran

[Ahmed.]

Dear Imran,
Feature no 3 came in which BSC version of E******* ?

BR//
Ahmed M

[haider79]

Thanks Ahmed,

I have single band -two configuration- cell here, i wanted to increase SDs from 2 to 3 but DB team said it is not possible! it is correct?

BR,

[Ahmed.]

Please check the post by Imran Rafique below. Check its point 1 & 3. I think you may get the answer, you need to check if the mentioned features are enabled at BSC level or not.

[Muhammad Imran Rafique]

Hi Ahmed,
its AXE PAR feature under these name





CME20BSCF ------INCRSDCCHCAP.

And it is available after i beleive R10 onwards.

BR//
Imran

[Muhammad Imran Rafique]

Yes haider,

As i clearly mentioend, you cannot cross limit (#of TRX configured).

So in this case your configured TRX are only 2, so this is your limit. In case you want to increase please activate AXEPAR INCRSDCCHCAP.

Cheers!
Imran