[U-04] Geospatial Applications for Societal Benefits

[U04-P10] Automated measurement of angular solar and sky illumination for remote sensing calibration using a motorized spectrometer

*Garid Zorigoo¹, Badamgarav Enkhbayar¹, Nobuyasu Naruse², Yukihiro Takahashi¹ (1.Hokkaido University, 2.Shiga University of Medical Science)

Keywords:Remote sensing, Angular illumination dependency, Solar calibration, Motorized spectrometer system

Accurate measurement of solar and sky illumination is crucial for remote sensing measurements; without proper calibration, variations in illumination can introduce spectral differences, affecting the data comparability. One of the significant challenges that is often overlooked is to calibrate solar and sky angular illuminations. Atmospheric factors such as cloud cover and aerosol scattering influence both the spectral composition and importantly angular distribution of incoming radiation. This study presents a motorized spectrometer system that captures spectral reflectance from standard reference plates at every 2-degree angular interval, enabling precise characteristics of angular illumination conditions. By synchronizing movement control of sensor orientation and simultaneous data recording, this approach can provide precise angular characteristics of solar and sky illumination. The collected data will be used in future correction algorithms, improving the radiometric calibration for remote sensing applications. This research establishes a framework for enhancing the accuracy of field-based remote sensing methodologies.