Radar target signature processing while measuring in near field

Radar target signature is usually measured in near field using step frequency radar system, and Fourier-based methods are conventionally applied to signature processing, but bias lies between near field and far field. RCS is an important signature, which may be extrapolated by simple signal processing algorithm, some results are shown; The one-dimension downrange profiles are also researched based on a model, which is the foundation of image technology. While two dimension scattering centers distribution is measured, ISAR processing technology is used. We often solve the question by digital signal processing, electromagnetic field methods are also necessary to calculate wave scattering and illuminating, if two approaches are combined, maybe some interesting results can be got, which is a trend.