MIMO Radar with Widely Separated Antennas

TLDR

MIMO radar employs multiple spatially distributed transmitters and receivers, distinct from multistatic radar, and with widely separated antennas it captures the spatial diversity of a target’s radar cross section. This article reviews recent work on MIMO radar with widely separated antennas. It explains the unique features of MIMO radar and illustrates them with examples. Noncoherent processing exploits spatial variations of a target’s radar cross section to provide diversity gain for detection and parameter estimation, while coherent processing can achieve resolution far beyond the radar’s waveform for target location.

Abstract

MIMO (multiple-input multiple-output) radar refers to an architecture that employs multiple, spatially distributed transmitters and receivers. While, in a general sense, MIMO radar can be viewed as a type of multistatic radar, the separate nomenclature suggests unique features that set MIMO radar apart from the multistatic radar literature and that have a close relation to MIMO communications. This article reviews some recent work on MIMO radar with widely separated antennas. Widely separated transmit/receive antennas capture the spatial diversity of the target's radar cross section (RCS). Unique features of MIMO radar are explained and illustrated by examples. It is shown that with noncoherent processing, a target's RCS spatial variations can be exploited to obtain a diversity gain for target detection and for estimation of various parameters, such as angle of arrival and Doppler. For target location, it is shown that coherent processing can provide a resolution far exceeding that supported by the radar's waveform.