1. Calibration of a polarimetric microwave radiometer using a double directional coupler
- Author
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Luisa de la Fuente, Eduardo Artal, Enrique Villa, Beatriz Aja, and Universidad de Cantabria
- Subjects
010504 meteorology & atmospheric sciences ,Radio astronomy receiver ,Microwave polarimeter ,Science ,Polarimetry ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Cosmic microwave background receiver ,symbols.namesake ,Optics ,0103 physical sciences ,Calibration ,Stokes parameters ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Physics ,Radiometer ,business.industry ,Microwave radiometer ,Astrophysics::Instrumentation and Methods for Astrophysics ,Polarimeter ,Radiometer calibration ,radiometer ,polarimeter calibration ,microwave polarimeter ,radiometer calibration ,radio astronomy receiver ,cosmic microwave background receiver ,symbols ,General Earth and Planetary Sciences ,Power dividers and directional couplers ,business ,Polarimeter calibration ,Microwave - Abstract
This paper presents a built-in calibration procedure of a 10-to-20 GHz polarimeter aimed at measuring the I, Q, U Stokes parameters of cosmic microwave background (CMB) radiation. A full-band square waveguide double directional coupler, mounted in the antenna-feed system, is used to inject differently polarized reference waves. A brief description of the polarimetric microwave radiometer and the system calibration injector is also reported. A fully polarimetric calibration is also possible using the designed double directional coupler, although the presented calibration method in this paper is proposed to obtain three of the four Stokes parameters with the introduced microwave receiver, since V parameter is expected to be zero for the CMB radiation. Experimental results are presented for linearly polarized input waves in order to validate the built-in calibration system. The authors would like to thank The Spanish Ministry of Science and Innovation for financial support provided through the grants ESP2015-70646-C2-2-R, ESP2017-83921-C2-2-R and PID2019-110610RB-C22
- Published
- 2021