DOA Estimation of Coherent Sources Using Difference Algorithm with the Uniform Circular Arrays

This paper describes a new technique to estimate the direction of arrival (DOA) of coherent signals using a uniform circular array. Such an array may be transformed into a virtual uniform linear array in mode space. By exploiting the property of the virtual uniform linear array, a difference matrix can be constructed, whose rank is only related to the directions of arrival of correlated signals. This method can resolve the uncorrelated sources and coherent sources separately. In this way a conventional algorithm can estimate the DOA of uncorrelated sources, while the proposed algorithm can estimate the DOA of correlated and coherent sources. Thus the output data of the array are used repeatedly, and more sources can be estimated with fewer sensors. The effectiveness of the method is illustrated through a number of numerical examples.