Wireless Local Positioning with SILO-Based Backscatter Transponders for Autonomous Robot Navigation

Abstract

In this paper, we present a concept for wireless local positioning with multiple backscatter transponders based on the switched-injection locked oscillator (SILO). It allows reliable localization and ego-motion estimation of autonomous robots in indoor and outdoor environments. We derive the range-doppler spectrum of the beat signal that is induced by a single transponder in a FMCW radar system. With multiple transponders, a localization network is created that allows multilateral and multiangulation based positioning. For an initial evaluation, we built a miniaturized transponder for the 24 GHz ISM band and proofed the concept with a straightforward measurement, including two transponders, a moving ground robot equipped with a FMCW radar system and a laser tracker reference.