Resonant Beam Enabled DoA Estimation in Passive Positioning System

TL;DR

This paper introduces a passive RF resonant beam system for high-precision indoor device localization, avoiding complex channel estimation and beamforming, and demonstrating millimeter-level accuracy through theoretical analysis and simulations.

Contribution

It proposes a novel passive positioning system using resonant beams for high-precision DoA estimation without complex channel estimation or beamforming.

Findings

Achieves millimeter-level positioning accuracy at 2m distance.

Surpasses traditional RF active systems in precision.

Validates system feasibility through theoretical analysis and simulations.

Abstract

The rapid advancement of the next generation of communications and internet of things (IoT) technologies has made the provision of location-based services for diverse devices an increasingly pressing necessity. Localizing devices with/without intelligent computing abilities, including both active and passive devices is essential, especially in indoor scenarios. For traditional RF positioning systems, aligning transmission signals and dealing with signal interference in complex environments are inevitable challenges. Therefore, this paper proposed a new passive positioning system, the RF-band resonant beam positioning system (RF-RBPS), which achieves energy concentration and beam alignment by amplifying echoes between the base station (BS) and the passive target (PT), without the need for complex channel estimation and time-consuming beamforming and provides high-precision direction of arrival (DoA) estimation for battery-free targets using the resonant mechanism. The direction information of the PT is estimated using the multiple signal classification (MUSIC) algorithm at the end of BS. The feasibility of the proposed system is validated through theoretical analysis and simulations. Results indicate that the proposed RF-RBPS surpasses RF-band active positioning system (RF-APS) in precision, achieving millimeter-level precision at 2m within an elevation angle of 35$^\circ$, and an error of less than 3cm at 2.5m within an elevation angle of 35$^\circ$.