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Operational weather radars are usually equipped with a radome to reduce the wind load on the antenna and to allow continuous operation under bad weather conditions. The study is focused on quantifying the impact on radar polarimetric measurements due to the presence of a radome. Analysis refers to the transportable X-band polarimetric radar of the Agenzia Regionale per la Protezione Ambientale (ARPA) Piemonte (ARX), which uses a 'bullet shaped' radome to provide environmental protection to the antenna and receiver apparatus system. Radar calibration is performed using wet and dry radomes. Differential reflectivity calibration results are compared with those obtained using the sun as a radiation reference source. Estimates have comparable mean values, with their differences being within the standard deviation. The paper describes a method based on the self-consistency principle that takes into account the loss induced by radome wetting due to rain to adjust the absolute calibration of the radar in real time. To verify how well this method overcomes the problem of excess attenuation caused by the presence of precipitation on the radome, two validation methods are presented. The first uses an empirical model to estimate the two-way wet radome losses for a qualitative comparison, with the corresponding losses obtained by the self-consistency principle. The second employs comparisons between radar and gauge rainfall accumulations with and without radome correction. This approach offers a clear understanding of the response of the correction, providing quantitative performance in a real case. [ABSTRACT FROM AUTHOR]

To design X-band radar systems as well as evaluate algorithm development, it is useful to have simultaneous X-band observation with and without the impact of path attenuation. One way to develop that dataset is through theoretical models. This paper presents a methodology to generate realistic range profiles of radar variables at attenuating frequencies, such as X band, for rain medium. Fundamental microphysical properties of precipitation, namely, size and shape distribution information, are used to generate realistic profiles of X band starting with S-band observation. Conditioning the simulation from S band maintains the natural distribution of rainfall microphysical parameters. Data from the Colorado State University’s University of Chicago–Illinois State Water Survey (CHILL) radar and the National Center for Atmospheric Research S-band dual-polarization Doppler radar (S-POL) are used to simulate X-band radar variables. Three procedures to simulate the radar variables and sample applications are presented. [ABSTRACT FROM AUTHOR]

Abstract: Recently, we proposed a novel remote sensing method for rainfall rate estimation in real time by means of tomographic processing applied to power attenuation measurements made across the microwave links defined by radiobase station networks for mobile communication systems. In this paper we analyze the results of a new tomographic algorithm that has been specifically developed for the typical topology of the urban radiobase station networks. Such algorithm has been tested on simulated specific attenuation (K) maps based on true polarimetric weather radar data. We considered 18, 23, and 38GHz for the carrier frequencies of the radiobase network and the weather data gathered by the POLAR 55C polarimetric radar located in Rome. [Copyright &y& Elsevier]