Study On Attenuation Correction And Ground Clutter Cancellation And Precipitation Type Classification Of X-band Dual-polarization Weather Radar

Since the60’s of last century, dual-polarization weather research and application has been rapid development. So, it will become the mainstream of the weather radar. Compared with conventional radar, dual-polarization weather radar has obvious advantages in precipitation system detection, data quality improvement, etc. In this paper, we use some experimental data of X-band dual polarization radar to carry out some research about X-band dual polarization radar data processing, such as attenuation correction, ground clutter cancellation, precipitation type classification. Main works are as following:(1) Setting threshold, Use echo parameter reflectivity factor ZH and differential transmission phase shift constant KDP to correction reflectivity factor ZH. Compared the attenuation correction results with S-band Doppler weather radar echo at the same time,same place and same space. We find attenuation correction results are close to the S-band radar echo.(2) Ground clutter is non-precipitation echo, it will affect the precision of radar quantitative or half quantitative analysis of precipitation. So, the ground clutter must be identified before we process radar data. In this paper, we use echo parameter reflectivity factor ZH and differential reflectivity factor ZDR to identify ground clutter that appeared when X-band dual polarization radar scanning bottom echo.(3) Use vertical profile of reflectivity factor to correct ground clutter and reduce the impact of ground clutter on precipitation echo. So as to improve the quality of the radar data, and is helpful to quantitative or half quantitative analysis of precipitation and identification of recognition.(4) Compared the scatter diagram of reflectance factor ZH (after attenuation correction and ground clutter correction) and phase shift constant KDP with the simulated relationship between corrected reflectance factor ZH and the phase shift constant KDP. We find the scatter diagrams after correction are more close to the simulated curve.(5) Use the fuzzy logic algorithm to identify the type of precipitation particles,4kinds of echo parameters are involved to obtain9kinds of precipitation particle types. This method can identify the type of precipitation particles in stratiform cloud and convective cloud. The results coincide with the theory of cloud microphysical structure.