A V‐Shaped Fourth‐Order Sparse Array Design for 2‐D Direction of Arrival Estimation

Degrees of freedom (DOF) serves as a critical metric for evaluating the design of sparse arrays. Developing novel sparse arrays with enhanced degrees of freedom and mathematically expressible structures constitutes a significant research direction in the field of direction of arrival (DOA) estimation. In this paper, an innovative V‐shaped sparse sensor array is proposed through the strategic adjustment of sensor positions within the array which is called V‐shaped fourth‐order linear array (VFLA). Compared to existing V‐shaped sparse arrays, the proposed configuration demonstrates superior degrees of freedom when exploiting the covariance of received signals for DOA estimation. Furthermore, relative to commonly used V‐shaped arrays and other sparse arrays, the VFLA exhibits not only higher degrees of freedom but also a larger array aperture, thereby enhancing the accuracy of two‐dimensional (2‐D) DOA estimation. Finally, simulation experiments validate the outstanding performance of the VFLA in 2‐D DOA estimation.