The performance of the GSM random access procedure

The performance of the GSM version of the slotted ALOHA random access protocol has been investigated by means of computer simulation. Investigations have been carried out neglecting and taking into account radio aspects such as the capture effect and mobile stations of different power classes. Diagrams have been produced showing the blocking, the throughput and the time between the initialisation and the successful end of the procedure as a function of the traffic load for different random access control parameter values. Blocking is very low for a wide range of traffic load but increases drastically at a certain critical load. The degree of blocking increase and the position of the critical point depend on the control parameter values and the capture ratio