非视距信号路径返回的栅格迭代扫描定位算法

Grid iterative scan localization algorithm with signal path return for NLOS

针对无线传感器网络在非视距环境下的节点定位问题,提出信号路径返回和栅格扫描迭代定位算法。在非视距环境下,通过增强未知节点和锚节点的发射信号相互搜索非视距节点,通过标记节点的相关信息区分节点。结合增强信号系数和路径返回信号强度得到锚节点接近理想通信信号传播模型下的信号强度。在Grid-Scan算法和路径返回得到信号强度的基础上,提出栅格迭代定位算法。通过Grid-Scan算法初步缩小定位区域并得到初始位置估计。通过栅格迭代扫描,不断缩小定位区域,直到区域内的栅格数量趋于稳定,从而估计未知节点的位置。仿真结果表明,通过信号路径返回,非视距环境下的节点邻居关系和信号强度得到优化,定位精度在栅格迭代扫描算法下进一步提高。

Aiming at the node localization problem of wireless sensor network(WSN)in the non-line of sight(NLOS)environment,this paper proposes signal path return and Grid-Scan iterative localization algorithm.In NLOS environment,by enhancing the transmission signals of unknown nodes and anchor nodes,the NLOS nodes are searched for each other,and the nodes are distinguished by the related information of labeled nodes.Combined with enhanced signal coefficient and path return signal strength,the signal strength of the anchor node close to the ideal communication signal propagation model is obtained.Based on Grid-Scan algorithm and the signal strength obtained by path return,the grid iterative localization algorithm is proposed.Grid-Scan algorithm is used to reduce the location area and get the initial position estimation.Through grid iterative scanning,the localization area is continuously reduced until the number of grids in the area tends to be stable,so as to estimate the position of unknown nodes.Simulation results show that the signal path return optimizes the node neighbor relationship and signal strength in the NLOS environment,and the grid iterative scanning algorithm further improves the position accuracy.