A Retransmission Cut-Off Random Access Protocol with Multi-packet Reception Capability for Wireless Networks

A retransmission cut-off algorithm for Slotted ALOHA random access protocol is studied in terms of the new packet generation rate, the number of retransmission trials and the Multi-packet Reception capacity. The retransmission cut-off is not needed for a stable operation of Slotted ALOHA if the new packet generation rate is below a critical limit. The values of these critical limits increase almost linearly with the increase of MPR capability. The throughput never reaches its maximum value if the new packet generation rate is less than the corresponding critical limits irrespective of the number of retransmission trials. The maximum throughput is attained by adjusting the number of retransmission trials, pertaining to the new packet generation rate exceeding the corresponding critical limits. A complete analysis for the new packet generation rate with the proper adjustment of the number of retransmission trials and the Multi-packet Reception capability that maximizes the channel throughput and stable operation is found. The stable and unstable operating regions in terms of the new packet generation rate, the number of retransmission trials and the Multi-packet Reception capability is devised. The throughput and packet rejection probability of retransmission cut-off Slotted ALOHA with Multi-packet Reception capability are also provided.