This reference presents a complete perspective on recent developments in synthetic aperture radar (SAR) signal processing technology, based on the contemporary use of multiple SAR systems, or a single SAR with array instead of single antenna elements. These techniques improve the generation of 3-D images and make possible additional capabilities, such as images of moving targets. The author draws on his own research to present innovative approaches for microwave remote sensing using multiple-antenna SAR. Coverage includes azimuth, elevation, and multiple-input multiple output (MIMO) multi-antenna SAR.