Increasing information content is an important scientific problem in modern observation systems development. Radar, or microwave, imaging, a technique which combines radar techniques with digital or optical information processing, can be used for this purpose. Drawing on their own research, the authors provide an overview of the field and explain why a unified approach based on wave field processing techniques, including holographic and tomographic approaches, is necessary in high resolution radar design. Such techniques use the complex field incident on an observation surface to produce a...