DOA estimation of multiple non-coherent and coherent signals using element transposition of covariance matrix

Up to date, investigation of direction of arrival (DOA) gains more effort on multiple signals rather than coherent signals, particularly coherent signals measured by non-uniform and circular arrays — which still remains room for exploration. In this study, a new approach using element transposition of the covariance matrix combined with the MUSIC algorithm was proposed to estimate DOAs of multiple coherent and non-coherent signals by an arbitrary symmetric antenna array. A balanced property of phase differences of the symmetric antenna array was discovered to de-correlate the received signals, and simulation was performed for linear and circular arrays. Here, we established a new method to estimate and distinguish the DOAs of both non-coherent and coherent signals with higher accuracy and resolution than other conventional methods.