DOA estimation based on a novel shifted coprime array structure

This paper proposes a novel array structure to shift the position of physical sensors through a special coprime array to achieve a high degree of freedom (DOF) with a low mutual coupling effect. The sensor position and consecutive DOF of the closed-form formula of the novel array structure are given. Specifically, when SL is odd, the consecutive DOF is 3 MN +2 M +2 N -1, and when SL is even, the consecutive DOF is 3 MN +2 M +2 N +( M -1). The numerical simulation results show that the proposed array structure has the highest continuous DOF and relatively low mutual coupling effects compared to three coprime array structures. Compared with the two nested array structures, although the continuum DOF is close, the mutual coupling effect is much lower than that of the two nested array structures. As a result, a better balance between DOF and mutual coupling effects is achieved, and better DOA estimation performance is obtained.