Thesis - Open Access
Master of Science (MS)
Department / School
Electrical Engineering and Computer Science
BRDF correction, drift est
Given their low level of temporal, spatial, and spectral variability, Pseudo-Invariant Calibration Sites (PICS) have been increasingly desired as data sources for radiometric calibration of Earth imaging satellite sensors. The temporal resolution for PICS data acquired by any sensor is limited by the amount of time required for it to make subsequent passes over the site. Consequently, for any given PICS, it can take many years of imaging to develop a sufficient amount of cloud-free data to perform radiometric calibration; this can be especially problematic for sensors in their early years after launch. This thesis presents techniques to combine Landsat-8; normally acquiring data for every 16 days, image data from multiple PICS into a single dataset with increased temporal resolution and is called “PICS Normalization Process” or PNP. Landsat-8 Operational Land Imager (OLI) data from six Saharan desert sites were normalized to the Libya-4 reference. The normalized data were then merged into a “Super PICS” dataset, and the estimation of calibration drift was derived. The results of the Super PICS dataset show that the temporal resolution of the calibration dataset can be increased by approximately a factor of three to four times. The normalization process was performed on radiometrically and geometrically corrected image data (“L1T” product), and also on the same image data corrected for BRDF effects using a quadratic function of the solar zenith angle and TOA reflectance over a region of interest. An additional uncertainty analysis was performed using the BRDF corrected image data based on the following parameters which are involved in this whole BRDF PICS Normalization Process: Worst-case histogram bin analysis, Temporal Uncertainty of each PICS, BRDF Super PICS uncertainty. The resulting uncertainties are within the currently accepted satellite calibration range, within 3% for all spectral bands. Overall, the process indicates a calibration drift for OLI within 0.15% per year, agreeing quite well with the calibration drift derived from the on-board calibrators.
Library of Congress Subject Headings
Artificial satellites in remote sensing -- Calibration.
Landsat satellites -- Calibration.
Imaging systems -- Image quality.
Includes bibliographical references (pages 81-83)
Number of Pages
South Dakota State University
Vuppula, Harika, "Normalization of Pseudo-invariant Calibration Sites for Increasing the Temporal Resolution and Long-Term Trending" (2017). Electronic Theses and Dissertations. 2180.