Performance Improvement of Zigbee for Wireless Sensor Network

Abstract

Wireless sensor networks (WSNs) are being deployed in many real-life applications, such as environmental monitoring, security and surveillance, industrial automation and control due to its low cost, small size and low power consumption. This has been possible due to the advent of: (i)the IEEE 802.15.4 standard, which defines the physical and medium access control (MAC) layers of the protocol stack and (ii) the ZigBee specifications, which cover the network and application layers. A major concern in wireless sensor network (WSNs) is energy conservation, since battery-powered sensor nodes are expected to operate autonomously for a long time, e.g., for months or even years. Another critical aspect of WSNs is reliability, which is highly application-dependent. In most cases it is possible to trade-off energy consumption and reliability in order to prolong the network lifetime, while satisfying the application requirements. In our thesis performance of Zigbee is enhanced with help of fuzzy logic and modified Zigbee is called Ffuzzy based Zigbee (FZBE). Residual energy, packet dispatch ratio, data delivery ratio and sensitivity are given as input to FIS system. Fuzzy logic is used to select optimum values of output parameters: transmit power, retransmission timeout, duty cycle and back-off time of each node on the basics of applied logic which increases overall performance of Zigbee. Perforamance evaluation of FZBE is carried out in Network Simulator (ns-2) software by calculating parameters like delivery ratio, average message latency and average energy consumption per message for both single-hop and multi-hop scenarios. Simulation results show that FZBE performs better in comparison with ADAPT with Zigbee and standard Zigbee for both single-hop and multi-hop scenarios. cases. Simulation and analytical results have also been included in this report.