A Generalized Extended MIMO Array Design Strategy for DOA Estimation

With the rapid development of new-generation communication technologies, Multiple-input multiple-output (MIMO) radar has attracted the attention of researchers in the field of array signal processing due to its unique signal model. In traditional array signal processing, most of the attention has been focused on the problem of increasing the degrees of freedom (DOFs) of difference virtual arrays by improving the array structure in passive sensing. In MIMO-based active sensing system, the DOFs offered by existing array structures are limited. To address this issue, we propose a generalized extended MIMO array design strategy which introduces a two-layer difference based on the signal characteristics of MIMO. The array construction in this strategy is flexible, and due to the inter-element spacing is extended, higher DOFs are obtained. Simulation results demonstrate the superiority of the proposed array design strategy,