Super-Resolution in RSS-based Direction-of-Arrival Estimation

For the evolving Internet-of-Things ubiquitous posi- tioning is a core feature. Hence, energy- and location-awareness are essential properties of wireless sensor networks (WSNs). In terms low power consumption received signal strength (RSS)- based localization techniques outperform timing-based local- ization approaches. Therefore, RSS-based direction finding is prospective approach to location-aware, low-power sensor nodes. However, RSS-based direction-of-arrival (DOA) estimation is prone to multipath propagation. In this paper, a subspace-based approach to frequency-domain multipath resolution is presented. Resolution of multipath components allows for a RSS-based DOA estimation considering the power of the line of sight (LOS) component only. The impact of the multipath channel is considerably reduced with our approach. In contrast to common broadband DOA estimation techniques, the presented approach does not need phase-coherent receive channels or a synchronized sensor network. Hence, the proposed super-resolution technique is applicable to low-power sensor networks and brings accurate positioning to small-sized and energy-efficient sensor nodes.