Low-Cost Beamforming and DOA Estimation Based on One-Bit Reconfigurable Intelligent Surface

TL;DR

This paper presents a low-cost, efficient method for DOA estimation using a single antenna and a one-bit reconfigurable intelligent surface, employing optimized beamforming and sparse reconstruction techniques.

Contribution

It introduces a novel one-bit RIS architecture and a genetic algorithm-based beamforming scheme for improved DOA estimation in NLOS scenarios.

Findings

Outperforms existing DOA estimation methods in simulations

Guarantees restricted isometry property in measurement matrix design

Achieves accurate DOA with simplified hardware

Abstract

In this work, we consider the Direction-of-Arrival (DOA) estimation problem in a low-cost architecture where only one antenna as the receiver is aided by a reconfigurable intelligent surface (RIS). We introduce the one-bit RIS as a signal reflector to enhance signal transmission in non-line-of-sight (NLOS) situations and substantially simplify the physical hardware for DOA estimation. We optimize the beamforming scheme called measurement matrix to focus the echo power on the receiver with the coarse localization information of the targets as the prior. A beamforming scheme based on the modified genetic algorithm is proposed to optimize the measurement matrix, guaranteeing restricted isometry property (RIP) and meeting single beamforming requirements. The DOA results are finely estimated by solving an atomic-norm based sparse reconstruction problem. Simulation results show that the proposed method outperforms the existing methods in the DOA estimation performance.