Array SAR 3D Sparse Imaging Based on Regularization by Denoising Under Few Observed Data

TL;DR

This paper introduces a novel 3D sparse imaging framework for array SAR that leverages denoising-based regularization and proximal gradient methods to improve reconstruction quality with limited observed data.

Contribution

It proposes a general framework using RED and state-of-the-art denoising operators for improved sparse reconstruction in 3D SAR imaging with few data.

Findings

Superior reconstruction performance demonstrated in simulations.

Robust convergence of the proposed algorithms.

Effective preservation of target structure information.

Abstract

Array synthetic aperture radar (SAR) three-dimensional (3D) imaging can obtain 3D information of the target region, which is widely used in environmental monitoring and scattering information measurement. In recent years, with the development of compressed sensing (CS) theory, sparse signal processing is used in array SAR 3D imaging. Compared with matched filter (MF), sparse SAR imaging can effectively improve image quality. However, sparse imaging based on handcrafted regularization functions suffers from target information loss in few observed SAR data. Therefore, in this article, a general 3D sparse imaging framework based on Regulation by Denoising (RED) and proximal gradient descent type method for array SAR is presented. Firstly, we construct explicit prior terms via state-of-the-art denoising operators instead of regularization functions, which can improve the accuracy of sparse reconstruction and preserve the structure information of the target. Then, different proximal gradient descent type methods are presented, including a generalized alternating projection (GAP) and an alternating direction method of multiplier (ADMM), which is suitable for high-dimensional data processing. Additionally, the proposed method has robust convergence, which can achieve sparse reconstruction of 3D SAR in few observed SAR data. Extensive simulations and real data experiments are conducted to analyze the performance of the proposed method. The experimental results show that the proposed method has superior sparse reconstruction performance.