Moment method analysis of near field adaptive nulling

A near field technique which can be used to evaluate the far field nulling characteristics of an adaptive phased array is investigated. The method of moments is used to analyze the performance of a sidelobe canceller adaptive phased array antenna operating in the presence of near field interference. Bandwidth, polarization, mutual coupling, and finite array edge effects are taken into account. Phased array near field focusing is used to produce an equivalent far field antenna pattern at a range distance of one to two aperture diameters from the adaptive antenna under test. It is shown theoretically that the near field adaptive nulling performance, with sources located on a test plane at one to two aperture diameters range, is equivalent to conventional far field adaptive nulling