Throughput Analysis of a Class of Multiaccess Protocol for Packet Radio Networks with Capture Effect

In random access protocol for packet communications, it is widely assumed that the collision between packets results in irrecoverable destruction of the packets involved. This assumption is overly pessimistic for packet radio networks since it does not consider the effect of capture in radio channels. Capture effect is the phenomenon by which when radio nodes of unequal powers transmit simultaneously, the transmission with higher power is received correctly. In this paper, the effect of capture on the throughput performance of an Optimum Channel Utilisation Multiaccess (OCUM) protocol based on the busy tone concept for fully connected Packet Radio Networks(PRN) is analysed. The throughput performance for two classes of users with different transmit power levels is studied through Markov chain analysis. The analytical expressions for channel throughput, idle rate and collision rate are derived and the numerical results are highlighted. The simulation results are found to agree well with the analytical results.