Innovative Adaptive Algorithms for Multipath Mitigation and Interference Suppression for GPS Receivers Navy SBIR FY2009.1 Sol No.: Navy SBIR FY2009.1 Topic No.: N091-022 Topic Title: Innovative Adaptive Algorithms for Multipath Mitigation and Interference Suppression for GPS Receivers Proposal No.: N091-022-0300 Firm: Integrated Adaptive Applications, Inc 2506 NW 19th Way Gainesville, Florida 32605 Contact: Yahui Zhu Phone: (352) 378-7549 Web Site: http://www.iaaincorporated.com Abstract: The satellite-based GPS systems are vulnerable to intentional and unintentional interferences. Much work has been done on the development of anti-jam techniques using adaptive arrays for GPS receivers. Almost all of the anti-jam techniques proposed are based on the standard Capon beamformer or its robust variations. To improve the interference suppression performance of broadband jammers and to increase the number of narrowband jammers that can be suppressed, STAP and the related SFAP techniques have been used with beam forming/null steering. Multipath mitigation is another important challenge for GPS receivers. If the multipath time delays are small, the direct and the reflected paths are highly correlated and the multipath can affect the accuracy of the GPS receiver significantly. However, none of the aforementioned adaptive array techniques can work well when the desired signal is highly correlated with its multipath signals. The main objective of this program is to develop innovative techniques for the effective mitigation of multipath effects on airborne anti-jam GPS adaptive antennas. The secondary objective is to develop, test and deliver a software-based simulation capability that realistically simulates a GPS receiver equipped with a small anti-jam GPS antenna array operating in a multipath and interference environment. Benefits: The novel GPS receiver we propose to develop has many advantages over its conventional counterpart and will have an impact on all applications involving precision positioning and velocity determination. A partial list of these applications includes airborne platforms, ground based systems, ship based systems, and hand-held systems carried by mountain and forest hikers. The benefits of this research will impact each of these example applications by simply making the GPS receiver more reliable and accurate. Return