Direct Transition from Acquisition to Ultra-Tightly Coupled GPS/IMU

Military aircraft navigation systems employing GPS and inertial sensors are desired to operate robustly under conditions of severe aircraft dynamics and severe signal jamming. Very tightly integrated systems architectures, often calledUltra-Tightly-Coupled systems architectures, have been proposed in order to enhance navigation performance and robustness. These architectures have demonstrated substantially improved performance under high levels of jamming and dynamics, in comparisonwith conventional architectures. However, under conditions where the GPS code tracking errors are large, e.g., during the transition from acquisition to tracking, the performance of such systems becomes relatively poor. This SBIR program will demonstratethe feasibility of markedly improving the performance of Ultra-Tightly-Coupled GPS-inertial navigation systems under conditions were code-tracking errors are large, and thus facilitating the transition from acquisition to Ultra-Tight tracking and providingincreased robustness in environments where there are high levels of jamming and dynamics. The architectures, processes, algorithms, and software to be developed will enhance the performance and robustness of military and commercial GPS-inertial navigationsystems. There is expected to be a broad market for these improved navigation systems.