An integrated communications and control system for unmanned aircraft systems (UAS) utilizes automatic dependent surveillance broadcast (ADS-B) technology. The prime objective of this system is to address safety concerns related to UAS sharing airspace with traditional aircraft. This system is capable of real-time traffic and weather updates in three-dimensional trajectories, and can be re-engineered for specific missions and applications.

The system relies on GPS signals to provide increased situational awareness and a self-separation assurance system to avoid accidents. It is built around a standard Garmin GDL 90™ Universal Access Transceiver (UAT), which is independent of other aircraft avionics and requires only a power feed from the aircraft. The system is also compatible with the RANGR™ XVR system, model FDL-978-XVR, from FreeFlight®Systems™.

The system is compatible at both 978 and 1,090 MHz, and projects real-time satellite 3D and 4D imagery using Internet network links. Other aircraft, either manned or unmanned, can send information to the UAS. The software interface uses the standard ADS-B message protocol. The system architecture is designed with a lightweight tablet display.

The technology automatically broadcasts a UAS exact position 120 mi (≈193 km) in every direction every 1 second, as opposed to legacy radar-based transponder systems that “sweep” for position every 12 seconds. Accurate to within 5.7 ft (≈1.7 m), the technologies integrate commercial ADS-B hardware, radio data-link communications, software algorithms for real-time conflict detecting and alerting, and a display that employs a geobrowser for 3D graphical representations.

This work was done by Ricardo Arteaga of Armstrong Flight Research Center. DRC-011-012


NASA Tech Briefs Magazine

This article first appeared in the January, 2015 issue of NASA Tech Briefs Magazine.

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