In wireless networks, contention-and-reservation schemes provitle promising implementations of packet switching, which efficiently multiplexes different classes of traffic. In this report, we present an access scheme to satisfy the QoS requirements for two classes of traffic during the contention-based communicat,ion. In this algorithm, different classes of users contend with other users for resources based on controlled class-dependent permission probabilities. We prove that our algorithm is stable for a large class of arrival processes. Under certain QoS requirements, we derive an upper-bound for the throughput for a general class of random access algorithms. We show that the throughput of our algorithm asymptotically approaches this upper-bound. We also consider the algorithm with a capture model in the presence of near/far effects and Rayleigh fading with lognormal shadowing. We present a class-distance-dependent permission probability, which provides location fairness, certain delay guarantees, and a good throughput.

Date of this Version

November 2000