Yuliya Averyanova

Connection of reflected radar signal with liquid-hydrometeor deformation rate

In this paper forces and processes in the atmosphere that lead to drop deformation and vibration are considered. The expression that allows to define the reflected radar signal power redistribution between electromagnetic wave polarization components received with orthogonal antennas of Doppler-Polarimetric radar is obtained. The expression can be useful for creating turbulence intensity values scale when wind related phenomena estimate with polarization characteristics of radar signal.

Statistical algorithm for turbulence detection using polarization features of radar reflections from rain

In this paper the algorithm for turbulence zones detection using polarization features of radar reflections from rain is presented and discussed. The algorithm is based on the method that considers the change of low frequency component of reflected from rain radar signal as the result of reflected electromagnetic wave polarization change. The proposed method can be realized with unipolarized radar system with single transceiving antenna. Method allows to reach the order of integral probability of error for common case of proposed algorithm about 0.1.

Doppler polarization radar methods for meteorological applications

In this article, we present a brief overview of polarimetry application in radar meteorology and a new concept of polarization measurements via the polarization spectrum (the reflected energy distribution over polarization components). The polarization spectrum can be used to obtain information about different processes in the atmosphere. In [8], the polarization spectrum is proposed for use with turbulence intensity measurements. In [9], the possibility of applying the polarization spectrum for drop size distribution is shown. The presented approach shows the polarization spectrum application for wind speed estimation, taking into account the phenomenology of drop fission in the atmosphere under different situations, including the wind influence.

Ambiguity of droplet fission and its resolution using Doppler-polarimetric signal processing in meteorological radar

In this paper the different situations in the atmosphere that lead to the drop fission are considered. The approach to resolve the ambiguity of droplet fission using Doppler-polarimetric radar is presented.

Segregating deformation of scattering rain-drops using several receive antennas with different polarization angles

In this paper, the connection between polarization properties of radar receiveing antennas and deformation/vibration of scattering rain-drops is studied. The mathematical modeling and computer simulation are made to prove that it is possible to influence onto the contribution of a vibration component into the receiving signal by selection of polarization angle of receiving antenna. The results of theoretical background, mathematical modelling and computer simulation are used to prove the relationship between polarization characteristics of the radar signal and atmospheric dynamic phenomena. The results are also useful for better understanding the classical tasks of radar polarimetry including estimating drop size and rainfall intensity.

Simulation of liquid hydrometeors' scattering power distribution in multi-polarization radar

In this paper, we have considered and studied potentials of the multi-polarization radar system. The system allows receiving signal at different polarization angles including principle polarization and orthogonal to principle polarization. The computer model of reflections from vibrating and deformed liquid hydrometeors was developed. The simulation results demonstrated the benefits of the system including better signal-to-noise ratio, possibility to estimate the degree of reflected signal depolarization caused by atmospheric dynamic phenomena, registration of vibrating component by selection of receiving antenna polarization angle.

An approach to hydrometeors discrimination with similar polarization properties within the resolution volume

In this paper the possibility to distinguish hydrometeors with similar polarization properties inside the reflecting volume and estimating their differential impact onto polarization properties of reflected signal is made. The results are important for different practical applications of radar meteorology including drop size distribution estimate, rainfall intensity estimate, wind speed measurement, turbulence and strong wind shear detection.

Polarimetric method to discriminate the drops on sizes within the resolution volume

In this paper we consider possibilities of radar polarimetry to solve different meteorological tasks including identification of atmospheric pfenomena microstructure and hydrometeor orientation, hydrometeors size measurement, wind related phenomena estimation. The potentials and restrictions of radar polarimetry are discussed. The approach that allows to increase informativity of polarization measuremens by distinguishing hydrometeors with similar polarization properties inside the reflecting volume and estimating their differential impact onto polarization properties of reflected signal is presented. The overvew of the polarimetric system with multiple receiving antenna system for aproach realization is done. The results are important for different practical applications of radar meteorology including drop size distribution estimate, rainfall intensity estimate, wind speed measurement, turbulence and strong wind shear detection.

Principle of drops discrimination on sizes and shapes within the resolution volume with radar polarimetry

In this paper we discuss and show possibility to define amount of liquid hydrometeors with particular sizes, shapes and orientation within the resolution volume with radar polarimetry. The approach to discriminate liquid hydrometeors inside the reflecting volume on their shapes and sizes taking into account polarization features of reflected radar signal was presented. Method is based on obtaining information about refraction index of the medium, information about backscattering from reflecting volme, receiving backscattered energy under different polarization angles simultaneously and then finding half-width of the convex of centrally symmetric body that is the support function of a convex surface of falling liquid hydrometeors. Method of radar polarimetry considered and presented in this paper deal with wind and wind related phenomena detection and estimate additionally to classic tasks of polarimetric radars. It is expected that the most benefits the proposed approach can bring when combination with Doppler methods of wind and wind related phenomena estimates.

Dynamics of drop polarization basis under atmospheric factors influence

In this paper we analize the influence of dynamic atmospheric phenomena on drops behavior. Then we discuss possibility to connect reflected signal characteristics with scatterer polarization basis taking into account polarization features of electromagnetic wave. Information about drop polarization basis helps to improve data analysis and interpretation about atmospheric state and processes including wind related phenomena when signal processing.