There is a DOA estimation problem. In the context of a uniform linear array, when the array element spacing is greater than the half wavelength, i.e., d=λ, the covariance matrix based on received signals will generate phase ambiguity using MUSIC/ESPRIT algorithm.

Then, I still want to have a try using MUSIC algorithm. Therefore, I need to construct a new virtual covariance matrix to realize the DOA estimation.

Actually, I am working on the Near-field DOA estimation with ULA, and I have already construct a Toeplitz matrix to form a virtual Far-field covariance matrix. BUT the virtual Far-field covariance matrix is based d=λ. So I want to search for a effective method to solve it.

Is there a virtual matrix construction method which can turn the original problem into a "d