Study On A MAC Protocol Of Wireless Sensor Network With Adaptive Duty Cycle

The rapid development of the micro-electro-mechanism systems, technologies of wireless communication, micro-sensors and embedded computing promotes the emergence and development of wireless sensor networks. Wireless sensor network (WSN) consists of a certain number of smart sensors which form a multi-hop Ad Hoc network by radio communications in sensor field. It can be used for sensing, collecting and processing information of monitored objects. The wireless sensor network has become one of the research hotspots in the industry and academia. It has shown a great prospects in the future.Media Access Control (MAC) Protocol, which decides how to share wireless channels, allocates the limited communication resource among sensor nodes, and it is a intensively studied topic in WSN. MAC Protocols in WSN are mainly classified into two types, namely, contention-based protocols and time division multiple access based protocols. S-MAC protocol is a typical contention-based MAC Protocol, being put forward to meet the power demand of WSN. However, as a protocol with fixed duty cycle, S-MAC does not perform well for scenarios with data flows fluctuating with time and location. In this thesis, we propose a novel scheme with adaptive duty cycle. Analysis and simulation results show that the improved protocol, by adapting with traffic load, reduces the latency and loss, increases throughput, and significantly reduces energy consumption.