Scalable System for Precision Direction-Finding, Anti-Jam, and Anti-Spoof

The Global Positioning System (GPS) is vulnerable to radio-frequency (RF) sources of interference and must be defended through electronic protection (EP) measures such as anti-jam (AJ) and anti-spoof (AS). The Phase I effort investigated antenna, electronic, and algorithmic designs for systems capable of supporting direction-finding (DF) measurements while simultaneously performing anti-jam and anti-spoof operations. Design characteristics that provided enhanced performance were identified and validated through simulations, and limited hardware measurements were obtained. Two antennas were compared and a brassboard system was developed for the superior design, which was fabricated and tested. GPS-based attitude (GPS/A) determination algorithms in conjunction with algorithms for direction-finding (DF), anti-jamming, and spoof detection and mitigation were demonstrated through simulations. For the follow-on effort, the Phase I algorithms and designs will be enhanced, and a modular and scalable hardware architecture capable of supporting adaptive antennas having between one and 16 ports will be built and demonstrated. An existing 12-channel system will be used to test algorithms while the final scalable prototype system is being built. The program will conclude with a real-time demonstration of the hardware under realistic conditions and will deliver a prototype hardware system together with two antennas having four and six elements.