Reconfigurable Intelligent Surface Aided Sparse DOA Estimation Method With Non-ULA

TL;DR

This paper introduces a novel RIS-assisted sparse DOA estimation method that works with non-uniform array geometries, using phase adjustments and atomic norm techniques to improve accuracy with minimal hardware.

Contribution

It proposes a new RIS-based DOA estimation approach that accommodates arbitrary array geometries and reduces hardware complexity compared to traditional systems.

Findings

Achieves higher DOA estimation accuracy than existing methods.

Works effectively with non-uniform and arbitrary array geometries.

Uses a semi-definite programming approach for sparse signal recovery.

Abstract

The direction of arrival (DOA) estimation problem is addressed in this letter. A reconfigurable intelligent surface (RIS) aided system for the DOA estimation is proposed. Unlike traditional DOA estimation systems, a low-cost system with only one complete functional receiver is given by changing the phases of the reflected signals at the RIS elements to realize the multiple measurements. Moreover, an atomic norm-based method is proposed for the DOA estimation by exploiting the target sparsity in the spatial domain and solved by a semi-definite programming (SDP) method. Furthermore, the RIS elements can be any geometry array for practical consideration, so a transformation matrix is formulated and different from the conventional SDP method. Simulation results show that the proposed method can estimate the DOA more accurately than the existing methods in the non-uniform linear RIS array.