Pseudo Lateration: Millimeter-Wave Localization Using a Single RF Chain

While radio-based indoor localization schemes achieve decimeter-scale accuracy, they typically require precise reference measurements, multiple infrastructure nodes, or a multi-RF-chain anchor. In this paper, we propose Pseudo LATeration (PLAT), an indoor localization protocol that requires only a single RF chain infrastructure anchor and does not require prior knowledge of the environment. PLAT leverages the directionality and propagation characteristics of millimeter-wave transmissions to relax the requirement of multiple infrastructure anchors and RF chains by constructing pseudo anchors from reflected signal paths. By combining these pseudo anchors with time-of-flight measurements for distance estimation, PLAT can localize a user's device in indoors. Our evaluation reveals centimeter scale location accuracy for typical office environments. In testbed measurements and simulations, localization errors are centimeter scale for distances up to 1.5 m and beamwidths at or below 8.6 degrees. Although accuracy decreases to decimeter scale with additional propagation distance, we show that multiple reflection paths can mitigate this effect.