Cumulant-based direction-of-arrival estimation using multiple co-prime frequencies

In this paper, we propose a novel direction-of-arrival (DOA) estimation technique based on multiple co-prime frequencies and fourth-order statistics of the received signals. The utilization of multiple frequencies provides virtual sensors at the receiver array, thereby resulting in extended aperture, higher number of degrees-of-freedom, and greater flexibility compared to the commonly used single frequency-based methods. The set of lags achieved from the resulting virtual antenna elements is further extended by exploiting higher-order statistics-based difference co-array approach. The proposed scheme yields the fourth-order difference co-array which offers a significantly greater number of lags compared to the sparse array techniques used by existing DOA estimation methods. Simulation results verify the effectiveness of the proposed technique.