Next-Generation Air Deployable Active Receiver (ADAR)

A crucial factor in sonar design is the benefit available from increased aperture. Current sonobuoys have been constrained to the A-size configuration. Development of the ADAR system has been a significant success in packaging and deployment of such acomplex sensor in the small A-size format. With the Next Generation ADAR, we propose to increase the physical aperture and add a vertical component, while maintaining as much of the original ADAR design as practical. The Next Generation ADAR apertureoffers significant horizontal ABF gain without the burden of long integration times needed by long horizontal apertures. Its vertical aperture offers the added rejection of vertical components of the noise (including reverberation). The increasedaperture over the existing standard ADAR allows processing at lower frequencies to take advantage of improved propagation. Thus, the Next Generation ADAR can provide significant passive and active performance in the littoral regions of the world. DuringPhase I, ORINCON demonstrated this improved performance through simulation. For Phase II, two prototype Next Generation ADAR units will be assembled and tested at sea. A third prototype will be assembled for addressing the mechanical aspects of thearray. In Phase III, the Next Generation ADAR will be taken to a production configuration and qualified for deployment by aircraft, surface ships, and submarines. Through the increased detection performance of the Next Generation ADAR, the Navy will offset reductions in the number of available assets and again be able to offer undersea superiority against a modern, quiet diesel-electric or air-independentpropulsion (AIP) submarine threat to our naval forces in the littoral regions of the world.