Bifurcation Control in PRMA Joint Voice-Data System using Multiple Transmission Power Levels

This paper addresses the stability, bifurcation properties, and performance improvement of the packet reservation multiple access (PRMA) protocol extendable for mobile satellite systems (MSSs). This protocol provides voice and data terminals wireless access to a base station over a common communication medium. Modified versions of the PRMA protocol have been the subject of extensive research. The ultimate goal is to apply the protocol to low earth orbit mobile satellite systems (LEO-MSSs), to provide communication services to users around the world. In this work, the bistable behavior of the PRMA protocol for mixed traffic with voice and data sources is investigated. It is shown that the equilibrium points associated with this protocol undergo bifurcations as the control parameters are varied. In order to increase the throughput of the multiple random access protocol, many researchers have proposed using multiple transmission power levels at the terminals in order to take advantage of the capture phenomenon. Here, we study the effect of using multiple transmission power levels and taking advantage of power capture phenomenon for controlling the system bifurcations. Bifurcation control using multiple power levels is shown to be effective in increasing the capacity of the system. Finally, a brief discussion of extending the proposed control to PRMA protocol with large delays is also given.