一种基于竞争的无线传感器网络低延迟MAC协议

SMAC协议周期性侦听和休眠的低占空比机制大大地降低了无线传感器网络的能耗，但却是以牺牲延迟和吞吐量为代价的。针对SMAC协议虚拟簇间调度不一致而导致的休眠延迟问题，提出并设计了一种低延迟协议LDSMAC，该协议采用全局同步机制使整个网络内的所有节点形成统一调度，保证了全网内的所有节点在相同时间激活，从而解决了数据传输中的转发停顿问题。仿真结果表明，相比于SMAC协议，LDSMAC协议在能耗略有增加的情况下，大大地降低了传输延迟，提高了网络吞吐量。

A Low Delay MAC Protocol Based on Contention for Wireless Sensor Networks

The low-duty-cycle scheme of periodic listen and sleep is able to significantly reduce the energy consumption of wireless sensor networks in SMAC,but it accepts some reduction in both latency and throughput.In order to improve the latency of SMAC caused by the periodic sleep between different virtual clusters,this paper designs a low delay sensor medium access control protocol.This protocol applies the globally-synchronized mechanism to follow the same schedule for all the nodes in the whole network.Therefore,all the nodes in the network can be active at the same time to solve the forward pause problem of data transmission.The simulation results show that in the case of the slightly-increased aggregate energy consumption,LDSMAC greatly reduces the transmission delay and increases the network throughput.