RSS-Based Localization using A Single Robot in Complex Environments

Abstract

This paper considers the problem of localizing a static transmitter using a robot with a single receiving antenna and a single communication channel in unknown complex environments. Existing solutions using Time-of-Arrival (TOA) and Angle-of-Arrival (AOA) rely on complex wireless communication systems with multiple receive antennas or multiple communication channels, which are not available for robots with off-the-shelf low-cost radios. This paper develops a localization framework using Received Signal Strength (RSS) to estimate unknown channel model parameters considering multipath fading and spatial-correlated shadowing effects. The robot moves along a predefined trajectory to collect RSS data. AOA information is also estimated and integrated with the robot SLAM (Simultaneous Localization and Mapping) results to improve the localization accuracy. Numerical simulations and experiments in an indoor environment are conducted. Results show that 90% of the estimation error is smaller than 2 m to localize a randomly placed transmitter in a 10 × 10 m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> area.