融合RSSI跳数量化与误差修正的DV-Hop改进算法

Improved DV-Hop Algorithm Based on RSSI Hop Quantization and Error Correction

为了提高DV-Hop算法在非均匀网络中的定位精度,提出一种基于RSSI跳数量化与误差修正的DV-Hop改进算法。改进算法首先利用节点间RSSI值与基准RSSI值的比值量化节点间跳数,使整数跳数转化为连续跳数,并在量化跳数的基础上对锚节点平均跳距进行重估;然后对各锚节点平均跳距进行加权处理以修正未知节点平均跳距;最后利用未知节点与最近锚节点的距离关系对未知节点坐标的估计误差进行修正,以进一步降低节点的定位误差。实验结果表明,相较于DV-Hop算法及相关文献,改进算法在相同的网络环境下能够有效降低累积误差对距离估算的影响,提升未知节点定位的精度;在不增加硬件开销的情况下,改进算法的相对定位误差比DV-Hop算法平均下降了20.7%。

In order to improve the location accuracy of DV-Hop algorithm in the uneven networks,an improved DV-Hop algorithm based on RSSI hop quantification and error correction was proposed.Firstly,the improved algorithm quantified the hop counts by the ratio of RSSI value of the nodes to the reference RSSI value,which converts the integer hops into continuous hops,and recalculated the average single-hop distance of anchor nodes based on the quantized hops.Then,the average single-hop distance of anchor nodes were weighted to revise the average single-hop distance of unknown nodes.Finally,the distance relationships between unknown nodes and nearest anchor node were utilized to correct the error of the estimation coordinates for unknown nodes,which could further reduce the localization error of unknown nodes.The experimental results show that compared with DV-Hop algorithm and comparative reference,the improved algorithm can effectively decrease the effect of cumulative error on distance estimation and enhance the localization accuracy of unknown nodes in the same network environment.The relative localization error of the improved algorithm is 20.7%lower than that of DV-Hop algorithm without increasing hardware overhead.