Study On The Parameters Of Polarization Radar In The Orientation Normal Distribution Of Small Spheroidal Raindrops

The information of precipitation particles,such as scale size and spatial orientation, are important meteorological observation of physical onlookers. Linear depolarization ratio and differential reflectivity factor, radar parameters of Dual polarization radar, are the important parameters to reflect the physical characteristics of precipitation particles. They can effectively reflect the spatial orientation and the particle size of precipitation particles. Due to the difference of transmitting and receiving mode between Dual polarization radar and Doppler radar.We can get more Meteorological parameters and weather information.There are two basic working ways of Dual polarization radar:In one way we can get the information of zh and Zdr. In the other we can have LDR. Zdr is not enough in terms of researching Micro-physical characteristics of the upper part of clouds particle. We can not determine the shape and spatial orientation of the particles only by Zdr. Therefore, we can have LDR to determine the shape and spatial orientation of the particles. So we can use the study of LDR and Zdr to inverse actual space particle orientation by the data of Dual polarization radar. This article redefines the parameters of the radar detecting particles, LDR and deduces the new expression of radar parameters such as LDR and Zdr, in the case that rotation axis orientation of small ellipsoidal particles is normal distribution and raindrop is Gamma raindrop size distribute. The main study is finding out how the spatial variation of rotation axis orientation change the LDR and Zdr in using numerical simulation method. It summarizes the trends and gives their corresponding physical explanation.We hope the result of the study can provide theoretical and inversion basis for improving the accuracy of Dual polarization radar measurements of precipitation and the inverting the actual spatial orientation of the particles.