Demonstration of a Local Carrier-Based Precision Approach and Landing System (LC-PALS)

Toyon Research Corporation, together with the University of California, Santa Barbara (UCSB) propose to demonstrate a GPS-denied Local Carrier-based Precision Approach and Landing System (LC-PALS) that enables 3-D position, navigation and time (PNT) for platforms within range of an aircraft carrier equipped with one or more ADEPT-compliant beacons. Unlike the Global Positioning System (GPS), which requires four satellite signals, the Adaptive Polarized Navigation (ADEPT) waveform enables PNT with just two beacons. In addition, a single ADEPT-compliant beacon is sufficient if the platform is equipped with a good reference time source.The Phase I effort demonstrated that LC-PALS will achieve 10-cm z-axis (altitude) accuracy, thereby enabling autonomous carrier landing capability under GPS-denied conditions. Moreover, the system has a low probability of detection and intercept (LPD/LPI), significant built-in anti-jam, anti-spoof, and multipath-mitigation capabilities, and is not prone to integer ambiguity and cycle-slip phenomenon that is of concern with other carrier-phase tracking systems. Furthermore, because the system makes use of the same hardware that is required for GPS processing, an ADEPT receiver can be fully integrated with GPS, thereby minimizing redundant hardware and enabling simultaneous operation with GPS, when available. While an inertial measurement unit (IMU) is not required for precision approach and landing, an onboard IMU can be used as an additional and complementary measurement source for improved attitude performance, especially during the end game. While the Phase I program verified the feasibility of LC-PALS, the Phase II program will demonstrate the system under realistic conditions.