Interferometric imaging in a compact radar range

Inverse synthetic aperture radars are capable of accurate three-dimensional imagery. The first two dimensions, range and cross range, can be realized with a typical system. The height dimension however, is often not practical for most applications, as the computation costs can become prohibitive. Multiple flight passes and a significant increase in memory and processor demands are limiting factors, especially when dealing with real-time systems. As an alternative method to three-dimensional inverse synthetic-aperture radar imagery, as well as other intensive topographic mapping techniques, interferometric processing can be performed with a fraction of the resources while providing a reasonable quality of height information. Images acquired at two elevation angles in an ultra-wideband compact range have been processed, and 'interfered' with each other. The resulting phase difference between these two images was then used to resolve scatterers located at various heights on the target. Some limitations are also discussed.