Potentials of frequency agile Ka and W band cloud radars

To study the potential for frequency agile techniques of Ka and W band cloud radars, a simple case of two frequency agile radars with two close frequencies is considered. It is shown that power measurements at two wavelengths separated by 10% in frequency can be used to estimate the maximal size of scattering particles. This difference is due to the resonance effects which are considered at Ka and W bands widely used in cloud remote sensing. The Doppler spectra at vertical incidence are analyzed as well. Additionally, power spectral differences in the Doppler spectra measured at close wavelengths can reach several dB. The differences do not depend on the mean wind velocity in the radar volume and allow obtaining particles´ size distributions. We also describe a frequency agile Ka band radar with the bandwidth from 30 to 36 GHz.