Circulation Retrieval of Wake Vortex Under Rainy Condition With a Vertically Pointing Radar

Knowledge of the aircraft wake vortex circulation is very essential for promoting the aviation safety and airport capacity. Under rainy weather condition, the raindrops are driven by the velocity of wake vortex, and it is possible to retrieve the intensity of wake vortex by sensing the velocity variations of raindrops. This paper proposes to use a vertically pointing radar to detect wake vortex generated under the rainy condition. In the method, the raindrops that give the major scattering contribution are identified as characteristic-size raindrops, and their velocities and accelerations are well estimated from the Doppler spectra. Then, the target parameter, circulation r, can be well retrieved by solving the motion equation of characteristic-size raindrops. Numerical simulation results verify the good performance of the retrieval method.