LAUSR

Currently, most acoustic positioning strategies are based on broadband coding and the pulse compression technique to obtain better accuracy and robustness against in-band noise. However, the accuracy and robustness of these systems are often seriously damaged in areas of low coverage and/or affected by multipath. This work proposes a high availability positioning algorithm (HAPA) that optimally processes the received signal to improve positioning results throughout the whole location area. This algorithm validates the Time-of-Arrival (ToA) from each beacon, corrects their Doppler shift, and compensates for multipath when it exists. If the number of validated beacons is enough to obtain a position, the algorithm tries to position with their optimal combination; if not, it tries to position by incorporating additional ToA candidates for the nonvalidated beacons. The HAPA performance has been evaluated through a set of experimental tests to compare its results with those obtained by the robust positioning algorithm (RPA) developed by the authors in previous work, and by a classical positioning algorithm (CPA) based on the emission of chirps. In particular, when using a mobile robot to follow trajectories that cross areas with low coverage and affected by multipath, the HAPA maintains availability of 97.89%, while the RPA drops to 83.25% and the CPA to 50.19%.