研究片内多径分离技术在基于RSSI定位中的应用

摘要

The Received Signal Strength Indicator (RSSI) based location is easy to be affected by multipath interference in wireless sensor networks. The traditional RSSI-based location methods usually increase the number of samples to resist multipath interference while few works are done on physical layer. This paper studies to separate subchip multipath components for RSSI-based location application, the direct path can be separated among multipath by despreaded using the first sample of each chip, after calculating the direct path's power the anti-multipath interference's RSSI value can be got. The theoretical analysis of the performance of separating subchip multipath, Signal-to-Noise Ratio (SNR) losses are presented. Finally, the simulation shows the variance of RSSI value calculated by the traditional method and the proposal in this paper, the variance of the proposed method is smaller than the traditional method under multipath channel environment.%无线传感器网络中基于接收信号强度指示(RSSI)的定位易受多径干扰.传统的基于RSSI定位方法主要通过增加测距样本来抵抗多径干扰,而在物理层研究抗多径干扰的较少.该文将片内多径分离技术应用于基于RSSI的定位中,通过抽取每个码片的第1个采样点进行相关解扩得到分离多径后的直达径,并求其功率得到抗多径干扰的RSSI值.理论分析其多径的分离能力,信噪比损失情况.最后通过仿真比较了传统方法与该文方法求得的RSSI值方差,该文方法在多径信道下的方差更小.