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Progress Towards a NIST Microwave Brightness Temperature Standard for Remote Sensing
Published
Author(s)
Derek A. Houtz, Dave K. Walker, Dazhen Gu
Abstract
We discuss developments at NIST towards improving the passive microwave brightness temperature standard. By reducing uncertainty we can provide a better calibration for improved congruency between future weather and climate monitoring radiometers. We discuss the calibration procedure, measured data, and various theoretical and simulated results that have led to improved understanding of the uncertainty contributions in the measurement. We overview a Monte Carlo simulation to determine minimum achievable uncertainty, an electromagnetic coherence analysis that helps to determine optimal measurement distance, and we will touch on other improvements in the works including an improved blackbody design. The achievable calibration source brightness temperature uncertainty is expected to be reduced from the current 0.7 to 1.0 K from 18 to 65 GHz to less than 0.3 K.
Houtz, D.
, Walker, D.
and Gu, D.
(2014),
Progress Towards a NIST Microwave Brightness Temperature Standard for Remote Sensing, ARFTG 84th Microwave Measurement Conference, Boulder, CO, [online], https://doi.org/10.1109/ARFTG.2014.7013422
(Accessed October 12, 2025)