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Doppler characteristics of micro-drones with L-Band multibeam staring radar

Unmanned Aerial Systems (UAS), commonly referred to as drones, are rapidly proliferating. The accessibility of this technology is bringing about new challenges for security and safety. It is the class of micro-UAS which are raising particular concerns. The reason being their small size and ability to fly low in a highly irregular manner makes them particularly difficult to detect with conventional wide-area surveillance sensors such as a scanning radar. Here, we use Holographic Radar (HR), a 3-D, L-Band, staring surveillance radar capable of achieving high detection sensitivity. Whilst HR is able to detect miniature UAS against a background of complex clutter, the necessary high detection sensitivity means that many other small moving targets are detected, birds being a principle example. Good Doppler discrimination is central to the ability to distinguish between genuine drones and other targets reported by the radar sensor. Here, results are presented showing the Doppler characteristics of rotary wing micro-drones in both land and sea clutter.