Main Beam Jamming Nulling in Phased Array Radars

Integrated Sensors Inc. and Syracuse Research Corporation propose to develop and demonstrate techniques that effect practical, operationally meaningful, simultaneous mainlobe/sidelobe jamming cancellation for existing radars while preserving target angularaccuracies and permit operation in littoral (clutter) environments. The primary emphasis will be: (a) investigate practical interference suppression techniques for use in existing radars against current and projected interference sources, (b) developarchitectural requirements, analyze and quantify detection and target angular accuracy, and (c) demonstrate performance estimates and architectural feasibility. Four associated architectures will be examined: (1) a modified sequentialSum-Difference-Auxiliary adaptation scheme for combined constrained multiple sidelobe canceler/mainlobe canceler operation with non-separable antenna patterns, (2) a Sum-Difference-Auxiliary architecture, but with the addition of pre-cancellation Dopplerfiltering to enhance clutter suppression, (3) a Sum-Difference-Auxiliary architecture and pre-cancellation Doppler filtering but with the addition of frequency subbanding to extend performance for wideband operation, and (4) an interference suppressionoption for very wideband stretch processing receivers. Our demonstration plan includes an experimental system including a phased array radar as part of a comprehensive Phase I and Phase II program, eventually leading to implementation of jammingsuppression processors for retrofit into existing Navy radars.The technology developed can become an integral part of many future radar system designs for both military and commercial applications. A variety of applications for shipboard, airborne,spaceborne and ground based passive receive systems can significantly benefit as well. Commercial applications for communications systems will also benefit from this technology development.