Research On A Heterozygous MAC Protocol To Prolong Network Lifetime And Reduce Delay In WSN

Wireless sensor networks(WSNs)are an indispensable part of the Internet of things(Io T).It is generally used to monitor the surrounding environment and perceive important events.In wireless sensor networks,nodes should quickly send the perceived data to the sink node to ensure the timeliness of event processing.As an important way to control the communication between nodes,MAC(Media Access Control)protocol has a great impact on node performance and energy consumption.Therefore,the research and design of efficient MAC protocol can prolong the network life and reduce the network transmission delay.Based on this,we propose a Heterozygous-MAC protocol,which can improve the network lifetime and reduce the network delay at the same time.The proposed Heterozygous-MAC(H-MAC)protocol has the following innovations:(1)In view of the high energy consumption of the nodes in the hot area within one hop from the sink node,which is easy to deplete the energy first and lead to the early death of the network,the H-MAC protocol proposes that in the network,the nodes at different distances from the sink node adopt different MAC protocols.By using the improved RI-MAC protocol in the hot area node and the improved X-MAC protocol in the subhot area within two hops and outside one hop from the sink node,the energy consumption of the hot area node is optimized,so as to prolong the network life.(2)Aiming at the low energy utilization of non-hot area nodes outside the two hop range from the sink node,H-MAC protocol provides two optimization schemes to optimize the energy utilization and the maximum end-to-end delay of wireless sensor networks.In order to reduce the delay of the whole network,the core idea of the two schemes is to increase the duty cycle of the nodes in the non-hot area of the network according to their residual energy.The difference is that the first optimization scheme optimizes the duty cycle of the non-hot area according to the given cycle time of the hot area,while the second optimization scheme finds the optimal duty cycle of the non hot area through the algorithm,and then determines the cycle time of the hot area through the algorithm.From the theoretical analysis and experimental results,compared with the existing research,the H-MAC protocol proposed in this thesis can prolong the network lifetime by 21%,improve the energy utilization by 23%and reduce the network delay by 9%.From the perspective of comprehensive performance,H-MAC protocol can not only prolong the network life,but also reduce the end-to-end delay.