ULA Fitting for MIMO Radar

Uniform linear array (ULA) fitting (UF) principle is a newly proposed sparse array (SA) design scheme that aims to design SAs using cascaded ULAs, based on which a number of SAs with desired capacity are devised. In this letter, we introduce the UF idea to design sparse MIMO arrays with reduced mutual coupling and increased uniform degrees of freedom. However, existing sparse MIMO array design approach requires that the transmit and receive arrays in MIMO radar have hole-free difference coarrays (DCAs), which is no longer the best choice for the UF principle due to the fact that SAs designed via UF cannot guarantee hole-free DCAs. Considering the difference coarray of the sum coarray (DCSC) concept, a novel sparse MIMO array design strategy which is suitable for the UF principle is proposed. Based on the proposed strategy, a new sparse MIMO array is designed. Numerical simulations verify the good performance of the proposed sparse MIMO array in high coupling scenarios.