Bi-level JOMP for DOA estimation in coprime array with off-grid targets

Abstract

The direction of arrival (DOA) estimation for off-grid targets in the coprime array, which can extend degrees of freedom, is studied. Among existing research results, joint orthogonal matching pursuit (JOMP) has obvious advantages in complexity, but drawbacks in accuracy. Therefore, a bi-level iterative algorithm is proposed to improve estimation performance of JOMP in this study. First, JOMP is executed to obtain the initial estimations of DOAs and mismatch parameters. Then, an iterative proximity searching is implemented to update target vectors to decline the residual further. After that, on the strength of results of the secondary iteration, the signal spectrum and mismatch parameters can be obtained through exploiting LS algorithm. Simulation results verify effectiveness of the proposed algorithm.

Keywords

• iterative methods
• direction-of-arrival estimation
• array signal processing
• approximation theory
• search problems
• target vectors
• secondary iteration
• signal spectrum
• mismatch parameters
• doa estimation
• coprime array
• off-grid targets
• degrees of freedom
• joint orthogonal matching pursuit
• bi-level iterative algorithm
• estimation performance
• iterative proximity searching
• direction of arrival estimation
• bilevel jomp