PRACTICAL METHOD FOR UPGRADING EXISTING GNSS USER EQUIPMENT WITH TIGHTLY INTEGRATED NAV-COM CAPABILITY

摘要

A practical method for adding new high-performance, tightly integrated Nav-Com capability to any Global Navigation Satellite System (GNSS) user equipment requires no hardware modifications to the existing user equipment. In one example, the iGPS concept is applied to a Defense Advanced GPS Receiver (DAGR) and combines Low Earth Orbiting (LEO) satellites, such as Iridium, with GPS or other GNSS systems to significantly improve the accuracy, integrity, and availability of Position, Navigation, and Timing (PNT) and to enable new communication enhancements made available by the synthesis of precisely coupled navigation and communication modes. To achieve time synchronization stability between the existing DAGR and a plug-in iGPS enhancement module, a special-purpose wideband reference signal is generated by the iGPS module and coupled to the DAGR via the existing antenna port.