MISR: In-Flight Radiometric Calibration and Characterization Plan

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MISSION OPSACQUIRE MISRCALIBRATIONMODE DATAACQUIRE MISRLOCAL MODEDATAPREFLIGHTMISR PREFLGTRADIOMETRICCALIBRATIONLEVEL 1AARPUPDATED PARAMS.• Radiometric calib.coefficients anduncertainties• SNR• Pixel nonunif.• Quality thresholdsSTATIC PARAMS.• Spectral param.• PSF• Fields-of-viewWEIGHTIN-FLGT RAD.CALIBRATIONOBCVICARIOUS CAL.HISTOGRAM EQCAL TRENDLEVEL 1B1 ALGORITHMSRAD. SCALINGALGORITHMSCENE STUDIES• PSF• Spectral in-bandscalingRADIANCECONDITIONINGALGORITHMCHARACTERIZATIONDATAANOMOLIESNOISE STUDIESSCENE RAD.ERRORS• Contrast target• Spectral content• Pixel non-uniform.• PolarizationCALIBRATION INTEGRITYTRACEABILITYQUALITY ASSES.LEV. 1B1 RAD.PROD. VALIDTN• Sensor cross-comp.• Desert scenes• Lunar observ.LEGENDIFRCCactivityOtheractivityInput orOutputTaskFigure 3.2. IFRCC program element breakdowns.3.4.1 In-flight radiometric calibrationMISR is routinely calibrated in flight to account for anticipated degradations in sensorresponse with time. Preflight calibration data are used to establish a prediction of the initial onorbitresponse. These data have less influence with time, as the trend is established with more andmore on-orbit measurements. For the preflight, OBC, and VC methodologies, spatially andspectrally featureless targets are used to establish the calibration response.3. Calibration overview26
Multiple methodologies are utilized in the in-flight program in order to reduce systematicerrors and to provide a measure of calibration accuracies. The OBC provides frequent timesampling (monthly) of the instrument radiometric response. These data will be indispensable inthe verification of sensor response stability following undesirable spacecraft events (if they shouldoccur), such as a maneuver which may cause sunlight to fall on the front-surface optical elements.In using these data, however, it must be verified that there are no differences in measured responsethan that which would be obtained in viewing an Earth-target. As a general rule, the most accuratecalibrations are obtained with the sensor operating under the same conditions as during sciencedata acquisition. This is not the case when the cameras view the diffuse panels, irrespective ofhow well the design specifications have been met. Stray light and front surface reflectionsbetween the MISR camera and calibration panel have the potential of introducing an error sourcein the calibration. By including other methodologies in the analysis, any such systematic bias isdetected.The VC data require good weather conditions, and involve a staff and instrument teamwhich must be transported long distances to suitable test sites. Aircraft underflights, althoughpotentially providing the most accurate calibrations, are typically limited due to costconsiderations. Coordination among other sensor teams is also required. For these reasons VCcampaigns are less frequent than the OBC experiments. Semi-annual VC campaigns are planned.Because vicarious experiments are less controlled (with unpredictable weather), clearly thesemeasurements are not a substitute for the OBC data. Rather, the data sets complement each other.HE utilizes Earth scene data to make slight adjustments to the response coefficients. Thisis done to remove striping that might otherwise be present in the radiance product. These data areused to refine the relative calibration of the pixels within each camera, but is not a substitute forthe absolute response determinations of the OBC and VC observations.Trending of the data is an important element of the calibration program. By considerationof previous calibration determinations, abrupt changes in sensor reported response is avoided.Without this element, variations from one reporting to the next would cause erroneousfluctuations in the retrieved radiances. It is believed that any real change of the instrumentresponse will be slowly varying with time (in the absence of a spacecraft event which results indirect solar illumination of the optical surfaces, or which creates significant contamination).Response coefficients produced from these four methodologies are combined to generate asingle representation of sensor response. The coefficients are used to update the ARP, which isthen delivered to the DAAC and used in any subsequent processing. The ARP is planned to beupdated monthly.3.4.2 Level 1B1 Radiometric Product algorithm developmentSensor calibration data are used in the production of the MISR standard radiance product,termed the Level 1B1 Radiometric Product. Although processing occurs at the DAAC, it is theresponsibility of the IFRCC team to provide the algorithms, which the MISR Science DataSystem Team turns into production software. The algorithms are broken down into two types. Inthe radiance scaling processing step, digital number (DN) values are converted to band-weightedIn-flight Radiometric Calibration and Characterization Plan, JPL D-1331527
Page 6: 10.4.2 Radiative transfer. . . . .
Page 9 and 10: 1. INTRODUCTION1.1 PURPOSEThis docu
Page 11 and 12: • MISR Algorithm Development Plan
Page 13 and 14: 2.1 MISR SCIENCE OBJECTIVES2. EXPER
Page 15 and 16: In addition to these modes, the ins
Page 17 and 18: Table 2.1. Level 1A productProductL
Page 19 and 20: Table 2.4. Level 1B1 Ancillary Radi
Page 21 and 22: 3. CALIBRATION OVERVIEW3.1 REQUIREM
Page 23 and 24: equally to filter pinholes or scatt
Page 25: PREFLIGHTDATAIFRCCactivityOtheracti
Page 29 and 30: laboratory environment. This includ
Page 31 and 32: 4. PREFLIGHT CALIBRATION AND CHARAC
Page 33 and 34: determination was originally planne
Page 35 and 36: Cause: The filters are non uniform
Page 37 and 38: is the affected area is about 30 pi
Page 39 and 40: 5. IN-FLIGHT RADIOMETRIC CALIBRATIO
Page 41 and 42: esponse functions will be verified
Page 43 and 44: the array. Dark current is expected
Page 45 and 46: OBC design effort. The actual uncer
Page 47 and 48: 5.2.1 High-altitude sensor-based ca
Page 49 and 50: laboratory measurements. In order t
Page 51 and 52: 6. LEVEL 1B1 RADIOMETRIC PRODUCT AL
Page 53 and 54: flight. Generation of the updated p
Page 55 and 56: 7. CHARACTERIZATIONThe radiance unc
Page 57 and 58: 7.1.4 PolarizationMISR has been des
Page 59 and 60: It is believed that the evaluation
Page 61 and 62: 8. CALIBRATION INTEGRITYCalibration
Page 63 and 64: The baseline CAM is the most useful
Page 65 and 66: had all lamps on, and the satellite
Page 67 and 68: 9. MANAGEMENT9.1 PERSONNEL ROLES9.1
Page 69 and 70: EurOpto (preflight radiometriccal.)
Page 71 and 72: PRINCIPALINVESTIGATORDavid J. Diner
Page 73 and 74: • Identifying/specifying all of t
Page 75 and 76: 10. REFERENCES10.1 MISR EXPERIMENT(
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10.3 IN-FLIGHT CALIBRATION METHODOL
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38. Vane, G., T.G. Chrien, J.H. Rei
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APPENDIX A. NOMENCLATUREThe followi
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A.4 CHARACTERIZATIONcalibration. Th
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G 0 , G 1 , and G 2 are the respons
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APPENDIX B. CALIBRATION MODE SEQUEN
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In Cal-Dark data are acquired over
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Config. Home Run is a commanding of
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Repeat for 200 line repeat times, t
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MISR: In-Flight Radiometric Calibration and Characterization Plan

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