目标检测传感器网络参数设计

通过理论分析,给出了目标穿越无线传感器网络防线时的被检测概率与传感器网络设计参数之间的关系,建立了传感器网络目标检测问题的数学模型.传感器网络所有节点均采用基于时间片的休眠/唤醒节能策略,使得节点在每个时间片以一定的激活概率进入活动状态.推导目标检测概率的计算公式表明,检测概率与传感器节点的密度以及节点激活概率均成正比.因此,在满足所需要的目标检测概率条件下,可以采用降低节点密度或者减小节点激活概率的方法来减少系统能耗.此外,建立了节点工作时间片大小与传感器网络能耗之间的关系式.由该关系式得出,在其他参数确定的条件下,存在一个目标运动速率的临界值.当目标速率小于此临界值时,网络能耗随时间片的增加而增大;当目标速率大于此临界值时,网络能耗随时间片的增加而减小.

Parameters Design in Sensor Networks for Target Detection

A relation between the detected probability and the design parameters of sensor networks when the target passes through the defense line of sensor networks is given and a mathematical model about target detection in it is established.All sensor nodes of the network employ the sleep/wake up' energy saving policy based on time slice,under which nodes enter active state with certain probability at each time slice.The formula calculating the target detection probability shows that the target detection probability is in proportion to both of the density and activation probability of the nodes,so the energy consumption of the system can be reduced by decreasing the node density or reducing the activation probability of the nodes under the condition that target detection probability needed is satisfied.In addition,the relation between the time slice length and energy consumption is created,which shows that the energy consumption increases with increasing the time slice when the velocity of the target is lower than a critical value;and the energy consumption decreases with increasing the time slice when the velocity is higher than the critical value.