基于弧参数约束的无线传感网络定位算法

An Improved Arch Parameter Constraint-Based Localization Algorithm for Wireless Sensor Network

针对现有的无线传感网络非测距定位算法在提高定位精度时,存在计算量大的问题,提出了一种基于弧参数约束的自适应三边定位算法。该算法首先将与未知节点连通的信标节点所构成平面分割成若干个三角形,采用APIT算法确定未知节点所在的三角形集合,选择周长最大的三角形的顶点作为定位所用信标节点。围绕3个定位圆重叠区域,对以未知节点为圆心的假设圆的弧高和弦长进行了多次估计,估计次数则根据未知节点所在区域大小自动调整。再以每条弦的垂直平分线和未知节点所在区域的交点作为位置估计值之一,最后取全部位置估计的均值作为定位结果。仿真结果表明该算法定位精度优于质心法和Convex-PIT算法。

Considering the computation burden when improving the localization accuracy of the range free schemes,an arch parameter constraint-based range free localization algorithm is proposed.Three non-collinear anchor nodes are firstly obtained by approximate point in triangulation test(APIT)and triangular perimeter comparisons.The arc para-meters of the assume circle of the sensor node are derived from those selected anchor nodes.Then the arc parameters are used to generate the chords on the assume circle of sensor node.Later,the chords’perpendicular bisectors and its corresponding approximated radius are applied to localize the positions within the proximity of the sensor node,and an averaging process is performed to get the final result.An adaptive mechanism that controls the approximation accuracy and computational burden at different constraint area is also introduced.Simulation results show that the proposed algorithm has better localization accuracy than the centroid localization and the convex-PIT algorithm.