Cognitive Radio-Based UHF/VHF Crosslink Enhancement for Satellites

To address the Air Force need for enhanced Global Positioning System (GPS) crosslinks, Physical Optics Corporation (POC) proposes to advance the development of a new Cognitive Radio-Based UHF/VHF Crosslink Enhancement for Satellites (CRUCES). In Phase I, POC developed the CRUCES cognitive radio architecture incorporating POCs spectrum sensing and dynamic spectrum access, and developed an operational concept that uses existing non-directional crosslink antennas, is compatible with legacy crosslink operations, and is suitable for integration with next generation GPS space vehicles. Key to the CRUCES design is a model of spectrum usage in the medium earth orbit (MEO) environment, developed in Phase I, which provides the situational awareness required to enable operation as a secondary user without interfering with other users of the band. Key results of Phase I demonstrated CRUCES can provide average data rates of up to 2 Mbps, to meet throughput requirements for GPS autonomous navigation and secondary payloads. In addition, POC demonstrated that the full and continuous connectivity across the GPS constellation needed for real-time command and control (C2) is feasible. In Phase II, POC plans to develop a brassboard CRUCES prototype and demonstrate enhanced UHF/VHF crosslinks in a simulated interference environment, reaching technology readiness level (TRL)-5/6.