More TRXs or Fourth sector- Radio Congestion Problem

[islam wagih]

Dear EXPERTS,
If we have radio congestion due to lack of resources, "Regardless taking cost in consideration" which is better from increasing no of channels "resourses"

Add more TRXs
or
Add fourth sector with minimizing azimuth angel of each antenna

I ask radio optimizer and told me that:
Increasing no of TRXs will add more Erlang than adding fourth sector- as "Erlang" from no of TRXs in one sector is bigger than "Erlang" from the same no of TRxs divided of two sectors due to that Erlang-B table following Poisson distribution.
for ex, Erlang from 4 TRXs is more than Erlang from (2TRXs +2TRXs)

when i asked him why? he told me that traffic theory is based on poisson distribution and ..... Really I didn't understand why?

Could any one help me to understand please?

[sabila]

If u have more (case in gsm)freq allocated from goverment
Prefer add trx than add sector 4.
With 4 sector probable quality is more bad than 3 sector(sector 4 usually using maio sector2 that make some interference with sector 2)




Sent from my GT-N7000 using Tapatalk 2

[raghchau]

Dear EXPERTS,
If we have radio congestion due to lack of resources, "Regardless taking cost in consideration" which is better from increasing no of channels "resourses"

Add more TRXs
or
Add fourth sector with minimizing azimuth angel of each antenna

I ask radio optimizer and told me that:
Increasing no of TRXs will add more Erlang than adding fourth sector- as "Erlang" from no of TRXs in one sector is bigger than "Erlang" from the same no of TRxs divided of two sectors due to that Erlang-B table following Poisson distribution.
for ex, Erlang from 4 TRXs is more than Erlang from (2TRXs +2TRXs)

when i asked him why? he told me that traffic theory is based on poisson distribution and ..... Really I didn't understand why?

Could any one help me to understand please?

Hi,
Adding TRXs is more beneficial for adding Capacity..One reason for this is that when you add sector, you require some additional channels like BCCH,CCCH,SDCCH etc which reduces its capacity also.

[sabila]

Yups.
Thats right but
For just only capacity add trx more preferable
2trx existing with config like
1bcch
2sdcch
2pdch
11tch----capacity 11tch = 5.84 erlang(fullrate.gos 2%)
Capacity 11tch=14.89 erlang (100halfrate.gos 2%)

If u add 2trx again u will add 16 channel (in some case you need to add sdcch channel)
But if no sd required again.you will have
27 tch----= 19.26 erlang(fullrate.gos 2%)
27 tch----= 43.99 erlang(100halfrate.gos 2%)

Sorry if erlang count is wrong.
But for the simple count like that




Sent from my GT-N7000 using Tapatalk 2

[Shakeel_15]

Hello,

Addition of fourth sector is not very efficient way. It can be seen on some very exceptional cases. Infact adding a new fourth sector is better to deploy one new site. Four sector site is not a like a one cell site it looks like two sites:)
For your query TRX Expansion is better and also check the feature/license of quad rate, in latest vendor releases you can run 4 Calls on one TS.

BR