Retrieval of rain intensity by three-frequency radar sensing

Three-frequency approach for radar sensing of liquid precipitation is proposed, which permits to retrieve a spatial profile of rain intensity. Results of numerical simulation of three-frequency radar sensing of rains are presented for different sets of operating wavelengths of radar and for range of rain intensity (0÷30) mm/h. It is shown that use of millimeter wavelengths is not reasonable due to strong signal attenuation at the large distances and/or for large values of rain intensities. However application of longer wavelengths permits to reduce influence of attenuation and to decrease measurement errors of rain intensity. In particular, maximal retrieval error of rain intensity is not more than 7 %.