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Realization of a Standard Radiometer for Microwave Brightness-Temperature Measurements Traceable to Fundamental Noise Standards
Published
Author(s)
Dazhen Gu, Derek A. Houtz, James P. Randa, Dave K. Walker
Abstract
We describe and demonstrate a standard radiometer for making microwave brightness-temperature measurements that are traceable to fundamental noise standards. The standard radiometer is based on a National Institute of Standards and Technology (NIST) waveguide radiometer for 18-26.5 GHz, fitted with an antenna to measure radiated power. The fraction of the antenna pattern subtended by the radiating target is determined by anechoic-chamber measurements in which we vary the temperature of the target and measure the received power. Sample measurement results with uncertainties are presented. The typical standard uncertainty for a brightness temperature of around 340 K is about 1 K. The approach should be extendable to other waveguide bands where NIST has radiometers and standards.
Proceedings Title
2012 IEEE International Geoscience and Remote Sensing Symposium, Munich, Germany,
Gu, D.
, Houtz, D.
, Randa, J.
and Walker, D.
(2012),
Realization of a Standard Radiometer for Microwave Brightness-Temperature Measurements Traceable to Fundamental Noise Standards, 2012 IEEE International Geoscience and Remote Sensing Symposium, Munich, Germany,
, Munich, -1, [online], https://doi.org/10.1109/IGARSS.2012.6350709
(Accessed October 16, 2025)