ABAL: Aerial Beacon Assisted Localization Of Wireless Sensor Networks with RSS Maxima
Yu Xu and Xiaoqiu Shi
Location is one of the most essential contexts for manyWireless Sensor Network (WSN) applications. Despite its potentiality in mobile beacon assisted localization, Unmanned Aerial Vehicle (UAV) still suffers from considerable performance degradation due to RF irregularity in 3D space and the long distance environment. In this study, we design and implement an aerial beacon assisted localization system, named ABAL, which is based on the RSS maxima generated by straight line movement of a common omnidirectional antenna with a very narrow radiation angle in vertical plane. ABAL takes advantage of the narrow vertical radiation angle of antenna to enhance the recognizability of RSS maxima, and calculates sensor location using the perpendicular relationship between the line from sensor node to RSS maxima and the straight line, tolerating RF irregularity and enabling effective localization in long distance environment. Instead of simulation, we developed a prototype system and conducted comprehensive experiments in real flights. The evaluation results show that an impressive improvement of 30%∼150% over RSS ranging based approach can be achieved with the minimum mean absolute error (1.8 m) close to the error of high-quality single point GPS (1.5 m).
Keywords: Wireless sensor network, localization, aerial beacon, unmanned aerial vehicle, RSS maxima.