Research, Improvement And Simulation Of Zigbee MAC Protocol

ZigBee is designed as a low-cost, low-power, low-data rate wireless network technology. ZigBee technology uses the globally available, license-free 2.4GHz frequency band, and it's physical layer and MAC layer based on the IEEE 802.15.4 standard for wireless personal area networks. Wireless sensor network is a combination of sensor technology, embedded, and now communication networks, wireless communications, distributed information processing technology, comprehensive network technology, providing people with a new, practical ways to access and process information. Once the sensor nodes deployed in a certain area, it will work in an independent state, so the sensor nodes to adapt to the life and performance of the network directly affects the overall network performance, and because a large number of sensor nodes are usually distributed in a certain area, so the sensor nodes need to lower the energy consumption, makes the structure simpler and adaptable.Media Access Control (MAC) protocol is in the bottom part of the network protocols, is one of the important factors to determine the network performance. For wireless sensor networks, to design simple, low energy consumption, adaptive MAC layer protocol is a strong focus of the study people, is currently one of the hot spots.This paper studies and analyzes three MAC layer protocol:IEEE802.15.4MAC (the Zigbee MAC), IEEE802.11MAC, S-MAC protocol. And simulates these MAC protocols using NS-2 simulation platform; analyses and compares their energy consumption, latency and packet loss performance. Finally, improve the IEEE802.14.4MAC protocol to reduce its energy consumption; adds a listen sleep cycle mechanism in the IEEE802.15.4MAC protocol. Simulation results show that the new protocol greatly reduces the energy consumption, and the new protocol si more suitable for wireless sensor networks.