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

Autor: Jordi Figueras i Ventura, Martin Lainer, Jacopo Grazioli, Zaira Schauwecker
Rok vydání: 2021
Předmět:
Zdroj: IEEE Geoscience and Remote Sensing Letters. 18:642-646
ISSN: 1558-0571
1545-598X
DOI: 10.1109/lgrs.2020.2981993
Popis: 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 $Z_{\text {dr}}$ , copolar differential phase $\phi _{\text {dp}}$ offset, and copolar correlation coefficient ( $\rho _{hv}$ )] 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 $\phi _{\text {dp}}$ offset and 0.4–0.5 dB for $Z_{\text {dr}}$ bias), as well as a drop in $\rho _{hv}$ 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 $\rho _{hv}$ 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.
Databáze: OpenAIRE