无线传感器网络中一种改进的DV-Hop定位算法

针对 DV-Hop 算法在无线传感器网络节点分布不均匀时定位误差比较大的问题，提出了一种针对 DV-Hop 的改进定位算法。该改进算法主要是利用 RSSI 测量技术增加锚节点；在给定约束下引入“可能存在区域”这一概念，并以该可能存在区域的面积作为目标函数，对未知节点的位置利用非线性共轭梯度法进行逼近，从而使节点定位误差达到最小。通过仿真验证了节点通信半径和锚节点比例对定位误差的影响，结果表明，该改进算法将节点定位精度提高了5％～10％。

An improved localization algorithm based on DV-Hop in wireless sensor networks

Due to high error of positioning in the uneven distribution of wireless sensor network node for the DV-Hop algorithm,an improvement for the DV-Hop algorithm is presented.The main idea of this improvement is to use the received signal strength indicator measurement technique to increase the anchor nodes;then,the concept of “region of existence possibility ”is introduced under certain constraints, especially,the area of “region of existence possibility ”is regarded as the objective function of optimization problem,which is solved by using the nonlinear conjugate gradient method to approach the position of a unknown node,to minimum the node positioning error.Simulation result shows a 5% to 10% increase in positioning accuracy under the impact of different node communication radius and anchor node ratio,which validated the improvement.