Calibration of the MODIS PFM SRCA for on-orbit, cross-track MTF measurement

Alexandre B. Braga, Robert A. Schowengerdt, Francisco Rojas, Stuart F Biggar

Research output: Chapter in Book/Report/Conference proceedingConference contribution

8 Scopus citations

Abstract

The SpectroRadiometric Calibration Assembly (SRCA) instrument performs spatial, radiometric, and spectral in-flight calibration of the MODIS PFM instrument on the TERRA satellite. In spatial mode, the SRCA is intended to characterize focal plane registration by measuring cross-track spatial shifts of individual detectors (channels), and in-track band centroid shifts. In this paper, we investigate the suitability of the SRCA to evaluate the MODIS MTF on-orbit. Using the SRCA to evaluate the MODIS MTF requires information on the optical quality of the SRCA itself, particularly since it is not designed specifically for MTF measurements. Because the SRCA illumination fills only 1/4 of the optical aperture of the MODIS system, the illumination conditions are significantly different from those of normal MODIS imaging. We characterize the SRCA's spatial performance by estimating its MTF from the pre-launch SRCA and Integration and Alignment Collimator (IAC) datasets, the IAC being assumed to be of significantly higher quality than the SRCA. This analysis shows that the SRCA, after calibration by comparison to the IAC, may serve as one source for on-orbit MTF measurements of MODIS PFM.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
PublisherSociety of Photo-Optical Instrumentation Engineers
Pages71-79
Number of pages9
Volume4135
DOIs
Publication statusPublished - 2000
EventEarth Observing Systems V - San Diego, USA
Duration: Aug 2 2000Aug 4 2000

Other

OtherEarth Observing Systems V
CitySan Diego, USA
Period8/2/008/4/00

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ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this

Braga, A. B., Schowengerdt, R. A., Rojas, F., & Biggar, S. F. (2000). Calibration of the MODIS PFM SRCA for on-orbit, cross-track MTF measurement. In Proceedings of SPIE - The International Society for Optical Engineering (Vol. 4135, pp. 71-79). Society of Photo-Optical Instrumentation Engineers. https://doi.org/10.1117/12.494230