Erlang B Blocking for one GSM Carrier
A GSM base station uses carriers of 8 TDMA users.
Tables for Erlang-B blocking probabilities give for 1% blocking probability
- 3.13 erlang for 8 channels (one carrier)
- 8.88 erlang for 16 channels (two carriers, or one carrier with half-rate speech codes)
If one user generates 100 milli-erlang, the base station can handle a maximum of
- 26 users with one carrier
- 74 users with two carriers
Many operators accept larger blocking rate.
For 5% blocking, 8 channels (one carriers) can handle 4.5 erlang.
The above numbers do not account for a margin needed to accept handovers from other cells.
