GSM Backhauling

HI Guys!

We need to give a solution to a potential customer (Telecom Operator) for GSM BACKHAULING . Number of remote BTSs will connect through Satellite ( DVB based solution with return channel) to BSC .Now i read about memotec's AbisXtender , and RAD's equipment for gsm backhauling over the satellite. I dont understand following statement tht i read in a paper .

"The ACE-3200 aggregates up to 16 E1/T1s at BTS/Node B locations or at base station hub-sites, dramatically reducing the number of E1 lines that the operator will need for backhaul."

ACE-3200 is RAD's solution for gsm backhauling.What i dunt understand in this statement is tht how how it reduce the # of E1 lines tht operator will need to backhaul?In both aggregating and non-aggregating scenarios # of E1 tht operator has to lease or own will be the same (according to operator's network size) .How these equip reduce the need to hav smaller # of E1s?.

Can anyone explain this?Help will be appreciated
Rgds

Taqqi

Hi Taqqi,

The BTS is always going to present it's backhaul as X number of E1s. Lets assume this is 16 for this example.

So with a standard (wired) approach we would have the following network:

[code:1]
BTS

---

[ 16 E1s ]---- BSC ---> GSM CORE
[/code:1]

So this means the operator has to provide 16 E1s, at the BTS site through to the BSC site. Tradionally these will be leased via a local opertaor.

I guess your solution will look like this:

[code:1]
BTS --[16 E1s]-- ACE-3200--[Satelitte]--ACE-3200--[16 E1s]-- BSC
[/code:1]

(I have assumed that the ACE is need both at the BTS site to convert E1's for satellitte and at the BSC site to convert back to E1s for the BSC)

This means that the E1 links are only present on the BSC site locally where the go direct to the ACE for satellitte transmission.. so the mobile operator no longer needs to lease the E1's fro a local fixed operator.

So now the mobile operator pays for the ACE boxes and the satellitte link rather then the 16 E1s.

Hope this helps

R[/code]

So wht u mean is tht E1 long distance charges will not apply here in ACE3200 solution and only local 16 E1s at BSC side will be required ? thts understandable..i need further help on this as to how much bandwidth does a GSM call takes?(in kbps) if we have 3TRX(tranceivers)/BTS how much calls can be terminated at one BTS if 7 out of 8 timeslots will be used for traffic channel (TCH)?
If we have 1E1 from BTS-->BSC how many GSM calls can b terminated on BSC successfully after which congestion takes place?
Check the following website it has AbisXtender calculator sheet

www.memotec.com/mem/abisxtender/3g.php?file=AbisXtender Calculator.xls

i've cracked this excel sheet to see the formulas used in this sheet
On G23 cell following formula is used to determine Bandwidth need to transport GSM Traffice from BTS to BSC through satellite
=G6*(G7*3+G8)*64*2/1000

Wht i dont understand is tht y G7 cell is multiplied with "3" and y 64 is multiplied with "2".Plz guide.wht i understand is tht multiplied y 2 shows both inbound and outbound traffice (uplink & downlink) but i cant understand G7*3 portion of the formula.

Thnx for ur help.

Rgds
Taqqi