BSC's trafic at Busy Hour

[wireless_houss]

Hi dear friends;

if i know the number of TRX installed in a BSC, how can i calculate the trafic that BSC can deliver at Busy hour,

THANKS

[scorpion]

BSC Traffic Erlangs = Average TRX Erlang @ BH * Number of TRXs.

+/-3 %.

[wireless_houss]

BSC Traffic Erlangs = Average TRX Erlang @ BH * Number of TRXs.

+/-3 %.

could you give me more details please

by the way


1 TRX=2.94 erlang(2% GOS )
2 TRX=8.2 erlang(2% GOS )

so 2*2.94 doesn't equal 8.2

so if i consider your formula there will be a mistake in my estimation.

[electron]

Hi dear friends;

if i know the number of TRX installed in a BSC, how can i calculate the trafic that BSC can deliver at Busy hour,

THANKS

Accumulate traffic of all the cells hourly then find the hour that BSC carried highest traffic this is your BSC busy hour(BBH) and its carried traffic.

[wireless_houss]

Accumulate traffic of all the cells hourly then find the hour that BSC carried highest traffic this is your BSC busy hour(BBH) and its carried traffic.

but the problem is that the BSC's trafic changes everyday...I wonder if there is a specific formula to estimate the bsc's capacity (in term of trafic) at BH

[firstmaxim]

could you give me more details please

by the way


1 TRX=2.94 erlang(2% GOS )
2 TRX=8.2 erlang(2% GOS )

so 2*2.94 doesn't equal 8.2

so if i consider your formula there will be a mistake in my estimation.

Traffic in Erlangs does not scale linearly with the number of circuits. This is a trunking principle. If you have twice the number of circuits, the traffic offered would more than double.

[wireless_houss]

i came up with an idea if i know the number if configured tch in the BSC i can find the capacity of my BSC in term of trafic according to Erl B table.

[s52d]

Hi dear friends;

if i know the number of TRX installed in a BSC, how can i calculate the trafic that BSC can deliver at Busy hour,

THANKS

Hi!
Normally, BSC is NOT limited by TRXes, if it is properly dimensioned.
Traffic on TRXes vary with time/weekday (residential area, rural area, business area)
so cells have different peak hours. Thus, sum of pak hour traffic per cell is well beyond
BSC peak hour.

Also, modern GSM systems, using all traffic steering mechanisms and HR-AMR can handle much more traffic per TRX as given by plain old Erlang formula for one single cell with no HR.

Unless this is funny configured BSC, it is limited by A interface capacity, number of
TRAnscoders and simmilar.

For example 1000 TRX can theoretically handle 7000 Erlangs with no problems (with big cells),
but I would put three STM-1 for A interface and 4500 transcoders to it.
depending on TRA capability, how different codecs(HR, FR, AMR, HR-AMR, WB-AMR ...) are handled, what are licenses,
edge configuration etc, some 4200 Erl voice is decent limit for it.

BR
s52d