Adaptive-ALOHA multiple access protocol for mobile satellite systems

After an introduction on mobile satellite systems, a short overview of time random multiple access schemes (i.e. pure- and slotted-ALOHA) is given and the principle of retransmission of collided bursts is described. The new developed adaptive-ALOHA system using a variable number of burst retransmissions is presented and discussed. The performance of the adaptive-ALOHA scheme is evaluated by simulation and it is shown that adaptive-ALOHA is a stable system providing higher probability of successful access than pure-ALOHA without retransmission.