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wael
2010-12-29, 04:12 PM
Dear GPRS Experts
How many subscriber will share one PDCH slot in the GPRS ?

firstmaxim
2010-12-29, 04:51 PM
Dear GPRS Experts
How many subscriber will share one PDCH slot in the GPRS ?

It depends whether you are referring to the uplink or the downlink.

For the uplink, there are two methods of assignment-static method based on bit map, and then there is the dynamic method, based on the 3 bit uplink status flag-USF. The count for USF is a maximum of 8. So, this precludes one PDCH to be shared by more than 8 users on the uplink.

For the downlink GPRS is limited by the 5 bit TFI (temporary flow identifiers). One can have a maximum of 32 TFIs per frequency. Also, there is another limitation on each PDCH. This involves the Timing index allocation offset (this has a maximum count of 16).

These are the limitations specified by the standards. However, practical considerations such as service type, quality, load and need for lessening congestion will limit operators to a fewer users per PDCH.

wael
2010-12-29, 05:12 PM
many thanks , it is clear Now

coursekec
2011-01-04, 01:48 AM
Very good explanation...