On the Effect of Radome Characteristics on Polarimetric Moments and Sun Measurements of a Weather Radar

Abstract

This letter illustrates the effects that the regular pattern of the metallic unions of a four-panel radome had on the polarimetric variables [differential reflectivity Z dr , copolar differential phase φ dp offset, and copolar correlation coefficient (ρ hv)] as well as on the sun measurements of a mobile X-band weather radar. In particular, we focus on the analysis of the spatial distribution of the biases and the temporal variability of the sun measurements. We show that the metallic unions result in a nonnegligible sinusoidal-like spatial variability of the estimated biases (on the order of 7 •-8 • for φ dp offset and 0.4-0.5 dB for Z dr bias), as well as a drop in ρ hv in rain and a large temporal variability in the power measured by sun scans. These effects are compared with the measurements collected without a radome and with the measurements collected with a seamless monoblock radome on the same radar system. It is shown that operating without radome, when possible, has a positive impact on the data quality, largely reducing the spatial variability of the biases and increasing the ρ hv in rain. Similar performances, without the inherent risks, can be obtained as well with a seamless radome. Nevertheless, regardless of the form of operation, we advocate for monitoring the data quality as accurately as possible if quantitative applications are desired.

Insights into wind turbine reflectivity and radar cross-section (RCS) and their variability using X-band weather radar observations

“…The next step consists of a stratification of the spectral and polarimetric signatures upon a given rotor speed threshold. Indeed, in the case of not-moving rotors, the WT spectral signatures are similar to those of a tall metallic tower (Gabella, 2018): very large and very stable co-polar correlation coefficient; small dispersion of the differential phase shift; stable and slowly varying horizontal, vertical and differential reflectivities; null spectral signature. An example of not-varying horizontal reflectivity can be seen in Fig.…”

“…In June a complete new seamless radome was installed. The improvements compared to the former radome, which was joined by metal units, are shown and discussed in Figueras i Ventura et al (2020b). Concerning power-related measurements, it is important to know that the attenuation of both radomes have similar values.…”

Insights into wind turbine reflectivity and RCS and their variability using X-band weather radar observations

“…In June a complete new seamless radome has been installed. The improvements compared to the former radome, which was joint by metal units, are shown and discussed in Figueras i Ventura et al (2020b). Concerning power-related measurements, it is important to know that the attenuation of both radomes have similar values.…”

Electromagnetic Performance Analysis of Inhomogeneous Radome Walls Considering Temperature and Ablation

“…The radome is an important part of the aircraft seeker, which protects the antenna array from the external harsh environment [1][2][3]. During the high-speed flight of aircraft, the airflow in front of the radome head is compressed, which generates a lot of heat.…”