Initial Performance Analysis of the At-Altitude Radiance Ratio Method for Reflectance Conversion of Hyperspectral...

Area of Science:

• Remote Sensing
• Geospatial Analysis
• Radiometric Calibration

Background:

• Surface reflectance conversion is crucial for remote sensing analyses.
• The empirical line method (ELM) is widely used but requires pre-calibrated samples.
• The at-altitude radiance ratio (AARR) method offers real-time conversion without ground targets.

Purpose of the Study:

• To evaluate the performance of the AARR method for surface reflectance conversion.
• To assess AARR accuracy under challenging illumination conditions using hyperspectral data.
• To explore potential improvements for AARR accuracy.

Main Methods:

• Utilized an onboard downwelling irradiance spectrometer on a small unmanned aircraft system (sUAS).
• Collected hyperspectral radiance data under varied illumination.
• Compared AARR-derived reflectance with ELM and ground truth (implied).

Main Results:

• AARR-generated reflectance accuracy was comparable to ELM under tested conditions.
• Observed errors were acceptable for many remote sensing applications.
• AARR demonstrated potential for large-scale automation and atypical flight conditions.

Conclusions:

• AARR is a viable alternative to ELM for surface reflectance conversion, offering significant operational benefits.
• Further research into radiometric and atmospheric corrections can enhance AARR accuracy.
• AARR shows promise for efficient, automated remote sensing data acquisition.