When wind turbines are located in close proximity to each other they can have an important impact on air surveillance radars.
Air surveillance radars detect moving objects (e.g. aircraft) by filtering out stationary objects using the Doppler effect. Since wind turbines rotate they impart a Doppler shift on the radar signal. As a result, nearby wind farms can desensitize radar and cause false targets to appear on the radar screen. This clutter also causes targets to escape detection.
We use advanced time-frequency signal processing techniques to discriminate target and clutter signatures. We are using these techniques to develop new algorithms for the Air Force Research Laboratory (AFRL) that suppress clutter to enable detection and tracking of aircraft near wind farms.