Robust Network-Assisted Positioning, Navigation and Timing (PNT)

The use of assisted-GPS (A-GPS) has been very successful in civilian cellular networks to improve time-to-first-fix (TTFF) and in environments where signals from the Global Positioning System (GPS) are inherently weak, such as indoor environments or under a canopy. While the use of A-GPS has been demonstrated for military systems, the availability of network-based data is not always guaranteed and, when available, the bandwidths may not be sufficient to quickly provide the necessary information to jumpstart the GPS receiver for acquisition and tracking. During this program Toyon will develop assisted-GPS algorithms that minimize the data necessary for GPS acquisition and tracking while enabling signal lock when the carrier-to-noise power density is low and/or when the jamming-to-signal power ratio is high. While algorithms and architectures will be developed that are compatible with today’s military receivers, additional investigations will also identify promising techniques for newer receiver designs that significantly improve performance in the presence of multipath, spoofing and jamming. Toyon will demonstrate the algorithms and architectures developed during the program using existing hardware, including a military GPS receiver. At the conclusion of the program a prototype design will be completed and will be ready for fabrication during the Phase II program.