Wind Pattern of Scanning Millimeter Wave Doppler Radar

Millimeter wave Doppler cloud radar is a new meteorological equipment. In the existing cloud radar researches, measurements in vertical direction and of reflectivity are most used, relatively less for scan model and Doppler velocity data. In this study, applications of cloud radar Doppler velocity are mainly discussed. Wave length of the radar used in this study is 8.6 mm, which is designed for scanning, so detection range is a relatively important indicator. Taking transmit power, data resolution and attenuation into account, in this radar low pulse repetition frequency is used and resulting in low Doppler detection capability with 3.4 m/s Nyquist velocity. Therefore, serious ambiguities are frequently encountered in Doppler velocities images, and not easily handled by popular dealiasing processes. For 3D wind detecting a special scan pattern suited for the scanning cloud radar is designed in this paper, and the corresponding retrieving method without dealiasing preprocess is given. In the wind pattern radar can get a series of RHI data at increasing azimuths, specially, the RHI data include only elevations between 45° and 90°, and are named “High-half RHI” (HhRHI). Based every two HhRHIs data at adjacent azimuths, 3D wind field can be retrieved by the Velocity Elevation Display (VED) method which is in principle similar with the VAD (Velocity Azimuth Display) method popularly used in weather radar wind retrieving.