无线传感器网络中基于超宽带的TOA/AOA联合定位研究

摘要

提出一种基于超宽带(ultra wideband,UWB)信号到达时间估计(time of arrival,TOA)/到达角度估计(angle of arrival,AOA)联合估计的无线传感器网络(wireless sensor networks,WSNs)定位方案,只需要一个参考节点就可以实现对其他传感器节点的2D相对定位,并且不需要时钟同步,适合于传感器网络节点的低成本设计需求.利用往返时间(round trip time,RTT)进行TOA估计,给出了基于多径检测的TOA估计算法；利用到达时间差估计(time difference of arrival,TDOA)进行AOA估计,因而无需借助复杂的天线波束赋形技术.同时,分析了定位误差模型对定位性能的影响,并通过IEEE 802.15.4a信道下的仿真实验进行了验证,结果表明了所提方案的有效性.%A novel localization scheme for wireless sensor networks (WSNs) is proposed based on the joint estimation algorithm of TOA (time of arrival) and AOA (angle of arrival) under UWB (ultra wideband) signaling. One reference node is enough for the proposed method to localize other sensor nodes in 2-dimension, and the synchronization of the network is not necessary, satisfying the low complexity requirement of WSNs. RTT (round trip time) is used to estimate TOA, and the multi-path detection algorithm for TOA estimation is presented. TDOA is adopted to estimate AOA, avoiding the complicated antenna beam-forming for AOA. Simultaneously, the error model to the localization performance of the proposed scheme is theoretically analyzed and tested under IEEE 802. 15. 4a channels. The results demonstrate the effectiveness of the proposed scheme.