Landsat Data Continuity Mission Calibration and Validation

The primary payload for the Landsat Data Continuity Mission (LDCM) is the Operational Land Imager (OLI), being built by Ball Aerospace and Technologies, under contract to NASA. The OLI has spectral bands similar to the Landsat-7 ETM+, minus the thermal band and with two new bands, a 443 nm band and 1375 nm cirrus detection band. On-board calibration systems include two solar diffusers (routine and pristine), a shutter and three sets of internal lamps (routine, backup and pristine). Being a pushbroom opposed to a whiskbroom design of ETM+, the system poses new challenges for characterization and calibration, chief among them being the large focal plane with 75000+ detectors. A comprehensive characterization and calibration plan is in place for the instrument and the data throughout the mission including Ball, NASA and the United States Geological Survey, which will take over operations of LDCM after on-orbit commissioning. Driving radiometric calibration requirements for OLI data include radiance calibration to 5% uncertainty (1 q); reflectance calibration to 3% uncertainty (1 q) and relative (detector-to-detector) calibration to 0.5% (J (r). Driving geometric calibration requirements for OLI include bandto- band registration of 4.5 meters (90% confidence), absolute geodetic accuracy of 65 meters (90% CE) and relative geodetic accuracy of 25 meters (90% CE). Key spectral, spatial and radiometric characterization of the OLI will occur in thermal vacuum at Ball Aerospace. During commissioning the OLI will be characterized and calibrated using celestial (sun, moon, stars) sources and terrestrial sources. The USGS EROS ground processing system will incorporate an image assessment system similar to Landsat-7 for characterization and calibration. This system will have the added benefit that characterization data will be extracted as part of the normal image data processing, so that the characterization data available will be significantly larger than for Landsat-7 ETM+

OLI Radiometric Calibration

Goals: (1) Present an overview of the pre-launch radiance, reflectance & uniformity calibration of the Operational Land Imager (OLI) (1a) Transfer to orbit/heliostat (1b) Linearity (2) Discuss on-orbit plans for radiance, reflectance and uniformity calibration of the OL

The Landsat Data Continuity Mission Operational Land Imager: Pre-Launch Performance

The Operational Land Imager(OLI) will be the main instrument on Landsat-8 when it launches in 2012. OLI represents a generational change from heritage Landsat instruments in its design but must maintain data continuity with the 30+ year Landsat data archive. As a result, OLI has undergone a stringent calibration and characterization campaign to ensure its characteristics are understood and consistent with past instruments. This paper presents an overview of the OLI design, its major differences from previous Landsat instruments, and a summary of its expected performance

MODIS. Volume 2: MODIS level 1 geolocation, characterization and calibration algorithm theoretical basis document, version 1

The EOS Moderate Resolution Imaging Spectrometer (MODIS) is being developed by NASA for flight on the Earth Observing System (EOS) series of satellites, the first of which (EOS-AM-1) is scheduled for launch in 1998. This document describes the algorithms and their theoretical basis for the MODIS Level 1B characterization, calibration, and geolocation algorithms which must produce radiometrically, spectrally, and spatially calibrated data with sufficient accuracy so that Global change research programs can detect minute changes in biogeophysical parameters. The document first describes the geolocation algorithm which determines geodetic latitude, longitude, and elevation of each MODIS pixel and the determination of geometric parameters for each observation (satellite zenith angle, satellite azimuth, range to the satellite, solar zenith angle, and solar azimuth). Next, the utilization of the MODIS onboard calibration sources, which consist of the Spectroradiometric Calibration Assembly (SRCA), Solar Diffuser (SD), Solar Diffuser Stability Monitor (SDSM), and the Blackbody (BB), is treated. Characterization of these sources and integration of measurements into the calibration process is described. Finally, the use of external sources, including the Moon, instrumented sites on the Earth (called vicarious calibration), and unsupervised normalization sites having invariant reflectance and emissive properties is treated. Finally, algorithms for generating utility masks needed for scene-based calibration are discussed. Eight appendices are provided, covering instrument design and additional algorithm details

Pre-launch Radiometric Characterization of the Operational Land Imager 2 (OLI 2)

OLI-2 is a 9 channel, pushbroom, filter radiometer with a 15 degree cross track field of view. This presentation discusses its radiometric characterization in the Ball-10 thermal vacuum chamber, including: NIST radiance traceability, signal to noise ratio and non-linearity, non-uniformity, and the stability of its response

Landsat-8 Operational Land Imager Design, Characterization and Performance

The Operational Land Imager (OLI) on Landsat-8 represents a generational change from heritage Landsat instruments in its design, while it maintains data continuity with the 40+ year Landsat data archive. It preserves the 30-m ground sample distance, 185-km swath width and VIS/NIR/SWIR spectral bands. Furthermore, data continuity resulted from extensive pre-launch and on-orbit calibration and characterization campaigns. This paper presents an overview of the OLI design, the pre-launch characterization results and the on-orbit performance

Pre-launch Transfer to Orbit Testing for the Operational Land Imager 2 (OLI 2)

The Transfer to Orbit Measurement assesses the stability of OLI-2 calibration sources between pre-launch and on-orbit environments. To accomplish this Transfer to Orbit, OLI-2 has two on-board calibration sources, the solar diffuser and the stim lamps. This unique Transfer to Orbit experiment includes calibrating the diffuser pre-launch using a heliostat that steers sunlight into a thermal vacuum chamber. This presentation discusses the transfer-to-orbit data collection, analysis and results from the pre-launch calibration

Radiometric Source Uniformity Characterization with Angular Scans: Landsat-9 OLI-2 Experience

Recent imaging pushbroom radiometers with up to 30000 detectors per band in multiple modules and with dynamic ranges of up to 14 bits are a significant challenge to flat field. While there are various methods both pre-launch and on-orbit by which uniformity correction can be estimated, pre-launch calibration collects offer some of the lowest uncertainties. The Landsat-9 Operational Land Imager-2 (OLI2) prelaunch radiometric calibrations conducted at Ball Aerospace utilized spectral sources, large integrating spheres and rotation stages. The combination of these tools enables the calibration of the instrument’s radiometric response for the full field of view and dynamic range for each of its spectral bands. The uniformity characterization data for OLI2 were obtained by continuous motion yaw scans at multiple elevation angles, multiple source signal levels and wider angular range while the instrument is in the thermal vacuum chamber. The source used for the collects was a well-controlled tungsten halogen lamp illuminated integrating sphere. The yaw scans enables a creation of a sphere uniformity map for every band. The the uniformity map is 1° by 2.1° zone centered on the integrating sphere port. This extent is larger than the field of view of a single focal plan module (FPM). Effectively these data collects are mimicking the on-orbit side slither collects that are done on-orbit only now the target is a well-controlled stable calibration source with traceable absolute radiometric accuracy, and minimal atmospheric transmission error. The results of the radiometric uniformity characterization of OLI2 will be presented. The report will demonstrate that with the new collect method more information can be obtained in shorter amount of time and it ultimately resulted in better characterization dataset for OLI2. Description of the processing method used and the detailed information extracted from the data about quality of OLI2 and the sphere source will be provided. The uniformity corrections parameters and associated uncertainties for these uniformity correction factors will be discussed

Emitted and Reflected Radiance Calibration of two Large Area Cavity Blackbodies Using the NIST TXR

The emissivity and radiance of two Large Area Cavity Blackbodies (LABBs) were calibrated using the NIST Thermal Transfer Radiometer (TXR) in a thermal vacuum chamber with a warm ambient background at Ball Aerospace and Technologies Corporation. In addition to calibrating these quantities for a single viewing configuration, the radiance and emissivity were measured with the TXR as a function of linear position from the center of the cavity and angular position relative to the normal to the cavity plane. These results and supported modeling will be presented