In-orbit performance assessment of day and night operation of GOCI

Abstract

Geostationary Ocean Color Imager(GOCI) are planned to be conducted during GOCI/COMS(Communication, Ocean, and Meteorological Satellite) in-orbit test period. GOCI performance assessment on the radiometric and MTF performance are operated by Korea Ocean Satellite Center(KOSC) which takes charge in the operation of GOCI.For the GOCI radiometric performance, gain and offset value stability of GOCI adiometric model, dark signal sensitivity, SNR check are planned to be assessed. On the basis of the test results measured at on-ground verifi cation tests and in-orbit performance assessment test, initial GOCI radiometric model is determined.GOCI nominal image acquisition at night-time is planned for the assessment of the solar straylight and development of GOCI-II which will be equipped dedicated detector and bandpass fi lter for night time image acquisition. GOCI solar straylight analysis result will be utilized for the design of GOCI-II night-time observation.MTF performance of GOCI has been evaluated during on-ground test. It is expected that about 20~30% of MTF performance will be degraded due to the limitation of attitude control capability of COMS bus-system by the analysis result at GOCI design. DedicatedMTF deconvolution process has been implemented into the GOCI INR(Image Navigation and Registration) S/W, one of the ground processing system. GOCI MTF performance is assessed including GOCI MTF Deconvolutioin processing.In this paper, we present the in-orbit performance assessment of day-time and night-time operation of GOCI in terms of radiometric performance, Straylight, and MTF including ground processing.