System and method for forming a beam and creating nulls with an adaptive array antenna using antenna excision and orthogonal Eigen-weighting

摘要

A system and method for forming a beam and creating nulls. The inventive method combines frequency domain suppression technology for narrow-band jammer rejection with orthogonal weighting using Eigen analysis for jammer nulling and signal beam-forming for an array antenna system. The inventive system is adapted for use with an adaptive array antenna having a plurality of radiating elements. The system includes a frequency domain suppressor connected to the array antenna and an orthogonal weighting subsystem connected to the frequency domain suppressor. In the illustrative implementation, signals received by each radiating elements are processed by an analog front-end and digitized. The frequency domain suppressor includes a Fast Fourier transformer (FFT) and a frequency domain suppressor for each element in the array. The frequency domain suppressor further includes a threshold evaluator which reads the signals output by the FFT's and provides threshold controls to the spectral suppressors. The orthogonal subsystem includes an adaptive weighting unit connected to the output of each of the spectral suppressors. The orthogonal weighting subsystem further includes an orthogonal weighting estimator for determining and optimal orthogonal Eigen-weighting to be applied to each of the adaptive weighting units. The outputs of each of the adaptive weighting processors are combined and inverse Fast Fourier transformed to provide one or more output beams and or one or more nulls in an efficient manner designed to leave the system with at least one degree of freedom for other functions.