On the performance of graph-based scheduling algorithms for packet radio networks

Abstract

Many published algorithms used for scheduling transmissions in packet radio networks are based on finding maximal independent sets in an underlying graph. Such algorithms are developed under the assumptions of variations of the protocol interference model, which does not take the aggregated effect of interference into consideration. We provide a probabilistic analysis for the throughput performance of such graph based scheduling algorithms under the physical interference model. We show that in many scenarios a significant portion of transmissions scheduled based on the protocol interference model result in unacceptable signal-to-interference and noise ratio (SINR) at intended receivers. Our analytical as well as simulation results indicate that, counter intuitively, maximization of the cardinality of independent sets does not necessarily increase the throughput of a network. We introduce the truncated graph based scheduling algorithm (TGSA) that provides probabilistic guarantees for the throughput performance of the network.