中文摘要：

空闲侦听是无线传感器网络能耗的主要原因之一,而占空比机制是减少空闲侦听能量损耗最主要的方法之一。提出了一种新的无线传感器网络异步MAC协议,称为PA-MAC（Passive Asynchronous MAC）,即被动异步MAC。PA-MAC通过采用接收方发起数据传输机制、异步占空比机制以及节点唤醒时间估计机制,降低了节点的工作占空比,提高了网络的能量有效性。在NS2网络仿真平台上对PA-MAC的性能进行了评估。仿真结果表明,在保持网络性能的前提下,PA-MAC能够进一步降低节点工作的占空比,进而减少节点的能耗。

英文摘要：

The problem of idle listening is one of the most concerned issues in wireless sensor networks,and the duty cycling mechanism is widely used to reduce energy consumption.We present a new asynchronous MAC protocol,called Passive-Asynchronous MAC（PA-MAC）.PA-MAC uses receiver-initiated data transmission scheme,asynchronous duty cycling mechanism and awakening time estimation scheme to achieve low duty cycle and high energy efficiency.Simulations have been done to evaluate the performance of the proposed new protocol,by which we can find out that,on the premise of keeping the network performance,PA-MAC can further reduce the nodes＇ duty cycle,thereby reduce the energy consumption.