I. Introduction
The effect of mutual coupling is mainly embodied in the interference of array manifolds. With the development of compressed sensing (CS) theory [1], [2], the algorithms based on sparse representation recovery (SRR) have been successfully applied to the DOA estimation. For the SRR-based algorithms dealing with DOA estimation under mutual coupling, they can be further divided into three subcategories: on-grid DOA estimation method [3], off-grid DOA estimation method [4] and gridless DOA estimation method [5].