RSS-Based Localization in Obstructed Environment with Unknown Path Loss Exponent

Received Signal Strength (RSS)-based ranging techniques have recently attracted a lot of attention because of their advantages in terms of low cost and easy implementation. The received signal strength highly depends on the path loss effect of radio wave propagation. When there is obstruction between transmitter and receiver, the signal power can drop significantly on the corresponding obstructed link, which degrades the accuracy of distance estimation. In this paper, we propose a novel RSS-based localization algorithm in obstructed environments with unknown Path Loss Exponent (PLE) based on Maximum Likelihood Estimation (MLE). The proposed algorithm can automatically detect the obstructed links between transmitter and receiver, and reduce the localization error caused by obstruction effect. According to the simulation results, our proposed method shows higher localization accuracy in obstructed environments as compared to other existing schemes.