Joint Estimation of Location and Orientation in Wireless Sensor Networks Using Directional Antennas

This paper presents a joint location and orientation estimation algorithm for a mobile robot (MR) equipped with directional antennas in wireless sensor networks (WSNs). The proposed algorithm utilizes the antennas' directivity and signals received from a set of distributed sensors to estimate the location and the facing direction of the receiver. The MR may use multiple directive antennas, or a single antenna whose beam can be steered electronically or mechanically. The received signals from each antenna, or antenna direction, are applied to a simple linear regression algorithm that decides the direction of the object for that particular beam scan. The process is repeated for different angles, and the results obtained are used to estimate the location and orientation of the MR. Moreover, error concealment techniques are used to improve the estimation accuracy by applying the local majority voting and connected graph algorithms. The obtained experimental and simulation results show that the proposed approach can estimate the location and orientation with high accuracy, especially at high signal-to-noise-ratio (SNR).