In this paper, a gridless DOA estimation method with coexistence of non-circular and circular signals is proposed by employing an enhanced sparse nested array, whose virtual array has no holes. The virtual signals derived from both sum and difference co-arrays are constructed based on atomic norm minimization. Simulation results are provided to demonstrate the performance of the proposed method.

DOA estimation; Enhanced nested sparse array; Virtual array; Atomic norm; Circular and non-circular signals