Performance analysis of IEEE 802.15.4 based wireless sensor networks

Abstract

This thesis investigates performance of the IEEE 802.15.4 standard in the context of wireless sensor networks (WSNs) deployed in pervasive monitoring. IEEE 802.15.4 has been widely acknowledged as the standard physical (PHY) and medium access control (MAC) layer specications for WSNs due to its simple protocol stack and low power operation. Mathematical models and computer simulations were devised to analyse the IEEE 802.15.4 MAC protocol and to improve its performance under dierent applications and operational conditions. First, the beacon-enabled mode of the protocol with acknowledgments (ACKs) was analysed using a discrete time Markov chain (DTMC). The proposed modelprovides a generalised platform to evaluate the impact of dierent network andMAC layer parameters and erroneous channel conditions on the performance ofthe protocol. Second, performance of the non-beacon-enabled mode of the protocolwas investigated both with and without ACKs. The outcomes of theseanalyses were then used to compare and contrast the performance of two operationalmodes. Third, impact of the presence of hidden nodes on the performanceof IEEE 802.15.4 based networks was examined. Using a DTMC model and networksimulations, it was shown that the throughput of the protocol is severelyreduced due to increased transmission failures caused by hidden nodes. Finally,a new hybrid MAC mechanism was proposed to improve the performance of theIEEE 802.15.4 standard in the context of recently emerged hybrid monitoring applications.Simulation based experiments show that the proposed hybrid protocolnot only outperforms the standard protocol, but also provides a reliable, energyecient and delay limited transmission mechanism for hybrid monitoring WSNs.This thesis has provided a platform for further studies on the performanceanalysis and application specic tailoring of the IEEE 802.15.4 standard in thecontext of WSNs.

Date of Award	2013
Original language	English