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The Improved Dual-view Field Goniometer System FIGOS
Jürg Schopfer1, Stefan Dangel2, Mathias Kneubühler3
1University of Zurich, Remote Sensing Laboratories, Winterthurerstrasse 190, 8057 Zurich, Switzerland. juerg.schopfer@geo.uzh.ch.
Sensors (Basel, Switzerland)
|November 23, 2016
Summary
This study introduces a novel dual-view field goniometer system for accurate bidirectional reflectance distribution function (BRDF) retrieval. This advancement enables precise remote sensing data correction and surface parameter estimation.
Area of Science:
- Remote Sensing
- Geophysics
- Optical Physics
Background:
- Earth's surface reflectance is anisotropic due to optical and geometric properties.
- Bidirectional Reflectance Distribution Function (BRDF) describes surface reflectance characteristics.
- Accurate BRDF is crucial for remote sensing data correction and parameter retrieval.
Purpose of the Study:
- To present the first dual-view field goniometer system for spectrodirectional measurements.
- To enable simultaneous collection of reflected and incident radiation at high resolution.
- To accurately retrieve surface-specific BRDF and characterize diffuse radiation.
Main Methods:
- Development and deployment of a novel dual-view field goniometer system.
- Simultaneous acquisition of hyperspectral angular distribution for reflected and incident radiation.
- Characterization of incoming diffuse radiation under various atmospheric conditions.
Main Results:
- The dual-view goniometer system successfully collected spectrodirectional datasets.
- Accurate bidirectional reflectance factors (BRF) were retrieved for an artificial target.
- Comparison with laboratory measurements validated the system's performance.
Conclusions:
- The developed goniometer system fulfills the requirement for accurate BRDF retrieval.
- Further improvements and standardization of goniometer systems and measurements are recommended.
- Intercalibration of goniometers is essential for consistent remote sensing data.
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