MISR: In-Flight Radiometric Calibration and Characterization Plan

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A.2 DATAA.2.1 Data acquisitioncamera configuration. The cameras have the capability to generate degraded resolutionground footprints by averaging adjacent samples (crosstrack) and successive lines (downtrack).Specific allocations of the averaging capabilities among the channels are referred to as cameraconfigurations.Global Mode (GM). A camera configuration (data averaging) mode capable of providingcomplete, continuous coverage of the sunlit Earth and consistent with the instrument power anddata rate allocations.Local Mode (LM). A camera observation mode in which high resolution images in all 4bands of all 9 cameras of selected Earth targets are obtained by inhibiting pixel averaging in allbands of each of the cameras in sequence, one at a time, beginning with the first camera to acquirethe target and ending with the last camera to view the target.Calibration Mode (CM). An instrument mode in which the flight photodiodes aresampled at high data rates (25Hz), and transmitted with camera data. There are four such modes.For Cal-North and Cal-South, the diffuse panels are deployed and viewed by the cameras andphotodiodes simultaneously. The forward and nadir cameras are calibrated at the North Pole, andthe aftward and nadir cameras are calibrated at the South Pole. Each instrument channel in thecameras being calibrated is cycled through the spatial averaging modes (1 x 1, 1 x 4, and 4 x 4), aswell as a sweep through all integration times. For Cal-Diode camera and diode data are acquiredduring Earth-observation; for Cal-Dark camera and diode data are acquired during dark-Earth(night) observations.A.2.2 Data product generationdata product. The final processed data sets associated with the various measured andderived geophysical parameters which are the object of a specified investigation and referred to asa higher level product than the measurement provided by the instrument.A.3 RADIOMETRIC PRODUCTradiance conditioning. This process is used to adjust the camera measured radiances forimperfections in the camera design. Specifically, point-source function (PSF) data are used toreduce the effects of scattering within the focal plane, in-band scaling is done to adjust for in-bandspectral profile nonuniformities with field angle and from one camera to another, and out-of-bandresponse subtraction is included within MISR standard product generation.radiance scaling. The process of converting DN data into a measure of incident spectralradiances, averaged over the MISR spectral response range.82Appendix A. Nomenclature
A.4 CHARACTERIZATIONcalibration. The set of operations which establish, under specified conditions, theradiometric, spectral, or geometric characterization of a sensor, as needed to understand theimpact of the instrument performance on the data or the derived data products.absolute calibration. The determination of calibration factors by comparison with astandard whose output is known in accepted physical (SI) units.vicarious calibration (VC). The radiometric calibration of an in-orbit sensor throughradiance determinations using in-situ or other transfer sensors (e.g., aircraft). Typicallydata are collected during an intensive field-campaign. The VC methodologies are:1) high-altitude sensor-based calibration in which helicopter or aircraft sensors are usedto map radiances and extrapolate to the required exo-atmospheric radiances;2) surface radiance-based calibration in which atmospheric and surface-measuredradiances are measured; or3) surface reflectance-based calibration in which atmospheric and surface reflectancecharacteristics are measured by the field instruments.For these methodologies, a radiative transfer code is used to extrapolate theobservations to a top-of-atmosphere value. The magnitude of the atmosphericcorrection increases for approaches (1) through 3).in-flight calibration. The calibration of an aircraft or satellite-based sensor while inflight. This may be through vicarious calibration exercises, or through use of an on-boardcalibration system.preflight calibration. The calibration of a sensor prior to launch using laboratorystandards.relative calibration. The determination of the correction by comparison with a standardwhose output is not necessarily known in physical units, but which is established in ratioor as a fraction of the value of the standard.characterization. The measurement of the typical behavior of instrument propertieswhich may affect the accuracy or quality of its response or derived data products.cross-comparison. The process of assessing the relative accuracy and precision ofresponse of two or more instruments. These activities are used to verify the calibration of theinstruments involved.Fidelity interval analysis. A statistical determination of the coefficients G and DN o ,along with their uncertainties, via an analyses such as that reported byChrien, N.C.L., C.J. Bruegge, and B.R. Barkstrom. Estimation of calibration uncertaintiesfor the Multi-angle Imaging SpectroRadiometer (MISR) via fidelity intervals. In SensorSystems for the Early Earth Observing System Platforms, Proc. SPIE 1939, April, 1993.In-flight Radiometric Calibration and Characterization Plan, JPL D-1331583
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10.4.2 Radiative transfer. . . . .
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1. INTRODUCTION1.1 PURPOSEThis docu
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• MISR Algorithm Development Plan
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2.1 MISR SCIENCE OBJECTIVES2. EXPER
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In addition to these modes, the ins
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Table 2.1. Level 1A productProductL
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Table 2.4. Level 1B1 Ancillary Radi
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3. CALIBRATION OVERVIEW3.1 REQUIREM
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equally to filter pinholes or scatt
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PREFLIGHTDATAIFRCCactivityOtheracti
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Multiple methodologies are utilized
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laboratory environment. This includ
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Page 33 and 34: determination was originally planne
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Page 39 and 40: 5. IN-FLIGHT RADIOMETRIC CALIBRATIO
Page 41 and 42: esponse functions will be verified
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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
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Page 61 and 62: 8. CALIBRATION INTEGRITYCalibration
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Page 67 and 68: 9. MANAGEMENT9.1 PERSONNEL ROLES9.1
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Page 71 and 72: PRINCIPALINVESTIGATORDavid J. Diner
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Page 75 and 76: 10. REFERENCES10.1 MISR EXPERIMENT(
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Page 81: APPENDIX A. NOMENCLATUREThe followi
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Page 91 and 92: Config. Home Run is a commanding of
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MISR: In-Flight Radiometric Calibration and Characterization Plan

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