基于摄影测量的水下无线传感器网络定位算法

Location algorithm for underwater wireless sensor network based on photogrammetry

针对水下无线传感器网络节点定位算法存在的水下测距技术实现难度大和未知节点获取多个信标节点位置信息时网络开销大等问题,提出一种基于摄影测量的并发式共线定位算法（PCL）.首先,利用矢量水听器阵列获得携带水下节点方位信息的信号;然后引入细菌觅食优化算法（BFO）对信源信号的波达方向（DOA）进行最大似然估计,在获得节点的方位估计后,算法通过判定未知节点与其周围信标节点的共线程度,进一步结合摄影测量原理对满足共线度阈值的未知节点进行坐标解算;最后将已定位的未知节点升级为信标节点进行迭代定位完成定位过程.仿真结果表明：算法在提高节点定位精度的同时,减少了未知节点定位对于信标节点数量的需求.

Aiming at the problem that the ranging technology is difficult to implement and the network overhead is great when the unknown nodes require multiple beacon node location information in the localization algorithm of underwater wireless sensor network,thus,a parallel photogrammetry-based collinear localization（PCL） algorithm was proposed.The algorithm firstly used the vector hydrophone array to gain the signal carrying the azimuth information of the underwater nodes,and then the bacterial foraging optimization algorithm（BFO） was introduced when estimate the direction of arrival（DOA） of the source signals with the maximum likelihood estimation.After obtaining the azimuth estimation of the node,the algorithm combined the principle of photogrammetry to solve the coordinates of the unknown node satisfying the collinearity threshold by judging the collinearity of the unknown node and its surrounding beacon nodes.Finally,the unknown nodes were upgraded to beacon nodes to complete the positioning process by iterative positioning.Simulation results show that the proposed algorithm can improve the positioning accuracy,and reduce the demand of unknown nodes for the number of beacon nodes.