Delay Analysis of IEEE 802.15.4 CSMA/CA Scheme in Wireless Multi-hop Sensor Networks

摘要

Analysis of IEEE 802.15.4 Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) scheme for multi-hop wireless sensor networks (WSNs) has received considerable attention recently, and most of these analyses focus on how to avoid hidden terminal impacts rather than the exact multi-hop characters. In this paper, we propose a stochastic analysis approach which contains 11 modified semi-Markov chains and one macro-Markov chain to evaluate delay of CSMA/CA scheme in multi-hop WSN's, presenting the accurate statistical results. Delay analyses of one hop together with two hops are proposed based on the assumption that nodes are randomly placed according to a Poisson distribution, and then we can easily extend the analyses to three hops or even higher hops. Comprehensive simulation results based on NS-2 are consistent with the predictions of these models.