DOA estimation of mixed coherent and uncorrelated signals exploiting a nested MIMO system

We propose a new scheme to estimate the directions-of-arrival of mixed coherent and uncorrelated signals exploiting a nested multiple-input multiple-output (MIMO) system. In the proposed scheme, the DOAs of the uncorrelated sources are first estimated using subspace-based methods, whereas those of the coherent sources are resolved using compressive sensing techniques. The proposed approach works for nonuniform linear sum coarrays and may resolve more sources than the number of coarray elements.