Throughput and Delay Performance Analysis of Packet Aggregation Scheme for PRMA

Packet reservation multiple access (PRMA) protocol is an implicit reservation MAC protocol. It is initially designed for voice packets in the cellular networks, but it is currently also used for data packets in OFDM based fixed wireless access networks. When it is applied for data packets, the system throughput depends on the size of packets and the number of consecutive packets. From the statistics of existent wireless data networks using PRMA protocol, it shows that the system throughput is quite low because of the inconsecutive small packets. In order to improve the throughput, packet aggregation scheme is considered to be applied in PRMA. Before designing packet aggregation algorithm, it is worth investigating the effect of packet aggregation scheme on the performance of throughput and delay. In this paper we develop a generic Markov chain model for PRMA with packet aggregation. Based on this model the throughput and delay are derived and analyzed. A numerical example is calculated, which illustrates the effect of packet aggregation on the throughput and delay with varying packet arrival rate. The results of the paper are valuable inputs for designing optimal packet aggregation algorithm, considering the tradeoff between throughput and delay.