IMPROVEMENT OF COUPLING CORRECTED DIFFERENCE BEAMS IN SMALL PHASED-ARRAYS

The corrupting effects of mutual coupling between radiating elements o f small phased arrays means that conventional aperture weighting schem es (Taylor, Chebyshev etc.) cannot be applied to small phased array an tennas to form low sidelobe sum and difference beams. The corrupting e ffects of mutual coupling can be removed by the determination of an in verted coupling matrix. This description of the couplings is not perfe ct. Thr imperfect coupling matrix description means the synthesised be ams are degraded. particularly difference beams where a deep look dire ction null is an important characteristic of the beam. The results of applying an adaptive algorithm to the coupling corrected array weight vector in order to enhance difference beam nulls is presented.