Application of sparse phased arrays to millimeter-wave radiometry

Although radiometry has been used in imaging applications for many years, it is only recently that radiometric imaging at millimeter-wave frequencies has become practical and relatively common. Unfortunately while millimeter-wave radiometers offer much better cloud, fog and solid object penetration than either visible or infrared systems, the obtainable spatial resolution is often too poor to produce a useful imagery. In this paper the authors present an array-based concept that has already demonstrated good image performance and is scalable to very large sparse apertures (for high spatial resolution) while still preserving a high frame rate. Approaches and techniques to help mitigate the effects of array sparseness are discussed in some detail.