Phase-difference-based 3-D Source Localization Using a Compact Receiver Configuration

Source localization has many important applications, especially in tracking and navigation. Trilateration, triangulation, and multilateration are three widely-used techniques for localization depending on the available information. The main drawbacks of these methods are the requirements of a large number of anchors and an elaborately designed layout. To accomplish the localization task with minimal resources while maintaining reasonable accuracy, we propose a 3-D source localization method with a compact infrastructure (prototype realized with 4 anchors located within an area of 2.5×20 cm2) by utilizing only phase-difference information. The proposed method first estimates the direction-of-arrival (DOA) of the target and then finds the candidate 3-D location along on the DOA by minimizing a cost function. This system is compared to the other two similar setups based on simulations and the experimental tests are carried out using acoustic waves. The results show that the proposed approach can achieve 3-D location error of 2.77 cm for a target at 0.5 m without synchronization between the transmitter and the receivers. The relatively small system size and sufficient location accuracy provide possibilities in controller tracking for virtual reality applications.