无线传感器网络服务质量的随机控制策略

为使网络具有给定的感知范围或覆盖率,必须保证WSN传感器具有一定空间密度,因此网络中活动的传感器数量可作为QoS的一种度量1]。在这种定义下,提出两种QoS控制方法,基于贪心算法的集中式控制方法和基于寿命的分布式随机控制方法。如果传感器能够存储运行状态信息或每隔一段时间能够交换节点寿命信息,前者可以获得最优的网络寿命;后者则通过交换初始传感器节点寿命,利用平均寿命信息随机调度活动的节点,从而延缓存活节点数的降低。仿真结果证实了这两种方法的有效性。

Stochastic policies for QoS control of wireless sensor network

One of the performance measures of QoS is WSNs spatial resolution,i.e.the number of the active nodes in the WSNs for the application requirements such as coverage and connectivity in WSNs.With this definition,we present two stochastic QoS control algorithms,one is based on greedy algorithm and the other is based on the expected WSNs lifetime.The first algorithm can gain the optimal network lifetime when each sensor can store all its running information or the sensors can exchange their expected lifetime periodically.With the help of the expected mean lifetime,the second algorithm gives a stochastic scheduling scheme which tries to keep sensors alive as more as possible while requiring few control information exchanges.Simulation results show that,our algorithms can gain longer lifetime of WSNs than the existed algorithms while keep the QoS performance.