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NASA NTRS · 20250004345

Operational Correction for the Temperature Dependence of A Class of Hyperspectral Radiometers

Abstract

The correction for temperature response of optical radiometers implies access to their working temperature (i.e., either the internal or ambient one with the radiometers in thermal equilibrium). With specific reference to a class of widely used hyperspectral radiometers lacking a thermistor to measure the internal temperature, this work investigated the potential for operational corrections relying on the ambient temperature derived from the radiometer dark digital counts. With the objective to keep within approximately 1% the uncertainty for radiometric corrections in the 400–800-nm spectral range, findings showed the applicability of the method for ambient temperatures higher than approximately 30°C. The alternative use of an ambient temperature proxy, determined from the air temperature incremented by a few degrees Celsius, was shown a valid solution to constrain the uncertainty of radiometric corrections to within 1% over the entire 0°–40°C interval.

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Giuseppe Zibordi, Marco Talone. 2025-12-12. Operational Correction for the Temperature Dependence of A Class of Hyperspectral Radiometers. https://ntrs.nasa.gov/citations/20250004345

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