RIS-ADMM: An ADMM-Based Passive and Sparse Sensing Method with Interference Removal

Abstract

The reconfigurable intelligent surface (RIS) has been a potential technology for future radar and wireless communication applications. In this letter, the passive sensing problem using wireless communications signal and RIS is addressed in the scenario with the interference from the wireless access point (AP). An atomic norm minimization (ANM) method is formulated to exploit the target sparsity in the spatial domain and estimate the direction of arrival (DOA), but the conventional semidefinite programming (SDP)-based method to solve the ANM problem is complex and cannot be realized efficiently. Therefore, we proposed a RIS-ADMM method as an alternating direction method of multipliers (ADMM)-based iterative method. The closed-form expressions are derived, and the interference signal is also suppressed. Simulation results show that the proposed RIS-ADMM method outperforms the compared methods in the DOA estimation performance with low computational complexity. The code about the proposed method is avaliable online https://github.com/chenpengseu/RIS-ADMM.git.

Joint Squared-Sine Function and ANM DOA Estimation for RIS-Based Sensing Systems

“…5 shows the estimation performance of the proposed SS-ANM together with four existing DOA estimation methods, and Table II shows their corresponding computational time. The four DOA estimation methods are SDP method [13], FFT method [20], l 1 -norm [21], l 2 and ANM [4]. It is seen clearly from Fig.…”

“…The integrated communication and sensing (ISAC) can partly solve this problem [1], and has received wide attention [2], in which passive sensing using wireless communication signals for direction-of-arrival (DOA) estimation is one of the hotspots [3]. The DOA estimation system using passive sensing is easy to implement, but the existing of multiple paths brings computational complexity and huge cost [4]. In this context, reconfigurable intelligent surface (RIS) is brought to confront this difficulty.…”