Sense and Avoid implementation in a small Unmanned Aerial Vehicle

This paper surveys candidate sense and avoid technologies to promote the safe and efficient integration of small UAV into the airspace shared by manned and unmanned aircraft. This endeavour addresses three issues: safety in the air and the environment; safety and privacy on the ground; air traffic capacity and congestion management. On the road towards fully autonomous UAV integrated in the global airspace, Unmanned Traffic Management acknowledges two functions, surveillance and sense and avoid, at two service levels. Given the wide variety of UAV and missions, the optimal solutions to address the three issues by the two functions depend on operation scenarios and the key variables are identified. FLARM is investigated in the field and compared to ADS-B, the leading aviation technology. Early tests were carried also on Wi-Fi as a sensing technology; other solutions coming from fields other than aviation are discussed too.