Queuing Analysis of Multi-channel S-ALOHA System with H2H and M2M Blending Traffic Arrivals

摘要

Based on queuing theory, we establish an analytical model of multi-channel S-ALOHA system in which H2H (Human to Human) and M2M (Machine to Machine) services coexist. Considering the collisions in access process triggered by multi-users, we make the packet transmission have dual randomness, one is the random selection of backoff counter, the other is the random selection of real number to be compared with persistence value. A new expression of successful transmission probability is presented to depict the competitive access among terminals, which can simplify the calculation. To investigate the interactions of H2H and M2M services, we compare their performance metrics under two media access modes where access channels are either shared or partitioned. To relive the congestions caused by simultaneous access of massive terminals in the case of channel partitioning, an adaptive access control algorithm for M2M services is proposed. Each M2M terminal adjusts its retransmission probability by changing persistent value dynamically to maintain system throughput at its maximum regardless of the traffic load. The results of this study can be used for a multi-channel S-ALOHA system design with H2H and M2M blending traffic arrivals.