Pre-Launch Absolute Calibration of CCD/CBERS-2B Sensor

Area of Science:

• Remote Sensing
• Satellite Calibration
• Radiometry

Background:

• Accurate calibration of Earth observation sensors is crucial for reliable data.
• The CBERS-2B satellite carries a CCD sensor for Earth imaging.
• Pre-launch calibration provides baseline performance data.

Purpose of the Study:

• To calculate pre-launch absolute calibration coefficients for the CCD/CBERS-2B sensor.
• To implement Brazilian image processing criteria for sensor calibration.
• To establish a baseline for future vicarious calibration and data monitoring.

Main Methods:

• Radiometric measurements were conducted in a satellite integration and test hall.
• An illuminated integrating sphere was used to capture calibration imagery.
• A relative calibration procedure was applied to equalize detector responses.
• Digital numbers (DN) were correlated with radiance levels to derive absolute coefficients.

Main Results:

• Pre-launch absolute calibration coefficients for the CCD/CBERS-2B sensor were successfully calculated.
• The calibration incorporated Brazilian image processing standards for the first time.
• Established baseline coefficients for comparison with future vicarious calibration results.

Conclusions:

• The calculated pre-launch coefficients provide a critical reference for CCD/CBERS-2B data quality.
• The application of Brazilian criteria ensures consistency with regional processing standards.
• Future comparisons will facilitate sensor performance monitoring and timely data updates for users.