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20th March 2000 at 23:16 #32535John SilungweGuest
Is a Traffic Channel (TCH) in a GSM mobile network given the same treatment as a circuit in an E1 trunk group when calculating Offered Traffic in Erlangs? Take for instance a GSM cell or sector with a maximum number of 28 TCHs, what would be the Traffic Offered in Erlangs if the grade of service is 2% in the Radio Interface? Please I need quick response to this question.
Thank you.15th December 2000 at 09:00 #32536Patrick MusondaGuest
This question John asked has been outstanding for sometime now without any one contributing to it. Can someone in the GSM Air Interface engineering fraternity say something please. I don’t think no one in Europe(the birth place of GSM technology) has seen this article. I expect engineers from Nortel, Nokia, Erricson, Siemens, Alcatel etc to give an answer to this question, or is it still under research?21st December 2000 at 18:58 #32537BrettGuest
Yes we normally treat a GSM tslots (TCH) the same as a fixed wire 64KBs ccts, etc etc.
There is some question as to whether Erlang B or C should be used, but generally in the Industry, Erlang B is used.
I have worked in GSM for 4 years with a number of companies and all have dimensioned TCH this way.
That said, there are some special situations, where Erlang B is used, but in a different way, specifically fractionally loaded networks. Here TCH’s on the BCCH carrier may be considered separately to hopping TCH’s in another group of channels.
Hope this helps11th March 2004 at 21:20 #32538farisGuest
can we use erlng b formul to calculate the capacity in GSM(mx no. of users)
if yes,are they talk in the same time
whats A=77.2 means,where A is the traffic intensity in erlang b