Universal Access Transceiver mottagare med GPS-tidsstämpel för multilateration-applikationer

To unlock the full potential of drone technology, enabling Beyond Visual Line of Sight (BVLOS) flight is required. However, for BVLOS flight to be safely integrated with manned aircraft, a robust and reliable airspace surveillance system is required. In the United States, two radio data links are used by aircraft and ground stations to communicate important information, Automatic Dependent Surveillance‑Broadcast (ADS‑B) 1090ES, and Universal Access Transceiver (UAT). Every aircraft is required to emit on one of the two data links. Ground-based receivers can be installed to monitor these data links, and extract information, such as the position, transmitted by aircraft. If the receivers can timestamp the received message, Multilateration (MLAT) can be used to verify the accuracy of the information and increase the reliability of the surveillance. This project aims at completing the ADS‑B 1090ES MLAT offering of Involi SA, by developing a receiver with timestamping for the UAT data link. It includes both the physical hardware implementation and the Field Programmable Gate Array (FPGA) signal processing implementation of a receiver capable of demodulating UAT messages, and capable of timestamping those messages with enough accuracy using a Global Navigation Satellite System (GNSS) receiver. Testing of the final implementation showed that the receiver was able to receive messages within the specification of UAT, and was able of timestamping the received messages with enough accuracy for MLAT.