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Landsat-7 ETM+ Radiometry Instrument-Based Stability/Calibration for Level-OR Characterization & Correction. The Art and Precision of ETM+ Radiometry 4. LPSO Path-Processing (PP) Based Background Characterization.
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Landsat-7 ETM+ Radiometry Instrument-Based Stability/Calibrationfor Level-OR Characterization & Correction The Art and Precision of ETM+ Radiometry 4. LPSO Path-Processing (PP) Based Background Characterization 1:00-1:45 PM Tuesday, 28 November 2006 Landsat Calibration Working Group (LCWG) Meeting At NASA Goddard Space Flight Center (GSFC, Bldg 33, Rm A128) Greenbelt, MD 20771 USA by John L. Barker, Ph. D. Landsat Associate Project Scientist, John.L.Barker@nasa.gov, 301-614-6610 LPSO:Land Cover Satellite Project Science Office, NASA/GSFC/614.4 Greenbelt, MD 20771 USA and David Landis SSAI, David.R.Landis.1@gsfc.nasa.gov, 301-614-6605 LPSO:Land Cover Satellite Project Science Office, NASA/GSFC/614.4 Greenbelt, MD 20771 USA Jeff Miller RSIS, Jeffrey.A.Miller.1@gsfc.nasa.gov, 301-614-6611 Instrumentation Science Branch, NASA/GSFC/614.6 Greenbelt, MD 20771 USA Jennifer Sun SSAI, Jennifer.B.Sun@gsfc.nasa.gov, 301-614-6618 LPSO:Land Cover Satellite Project Science Office, NASA/GSFC/614.4 Greenbelt, MD 20771 USA John Barker: 1) 2)
Agenda of Workshop on The Art and Precision ofLandsat-7 ETM+ Radiometry • 9:00 1. Approach to On-Board Characterization of ETM+ • 10:00 2. Landsat-7 ETM+ MOC and PCD Telemetry • 11:00 3. IAS-Based IC Lamp Characterization • 12:00 Lunch • 13:30 4. Path-Processing (PP) of ETM+ Background • 14:30 5. PP-Based IC Lamp Characterization John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Thanks for Multi-Year SupportTalk 4. LPSO Path-Processing of ETM+ Background LPSO Contract personnel Dave Landis, Jen Sun and Jeff Miller Mission Operation Center (MOC) Delta-I imaging collects & on-line telemetry access USGS EDC Image Assessment System (IAS) Creating , filling and maintaining the Landsat-7 IAS Oricle Database NASA support for LPSO Analysis, modeling & algorithm development Landsat Project Scientist Recognizing need for team & continuity John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Overview of Talk 4. Path-Processing of BackgroundThe Art & Precision of ETM+ Radiometry Why is background important? Net radiance is calculated on every scan At low radiance background is significant Within-scan background spectra Normal 500 minor frame (mf) IAS background Before, during and after DC Restore (DCR) for forward and reverse scans Path-processing (PP) Along-track stability, precision IAS Background Trending John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Landsat-7 ETM+ Radiometry Talk 4. LPSO Path-Processing of ETM+ Background IAS Shutter Bkgds are not constant We do not know why John Barker: 1) 2)
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B1D15_BH IAS Database, Non-Random
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B2D12_BH IAS Database, Non-Random
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B3D8_BH IAS Database, Non-Random
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background SD_B3D8_BH IAS Database has outliers
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B4D7_BL IAS Database, Decreasing
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B5D14_BH IAS Database, Non-Random
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B7D9_BH IAS Database, Non-Random 2-State
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background B8D27_BH IAS Database, Non-Random Outliers
IAS Background TrendsTalk 4. LPSO Path-Processing of ETM+ Background SD_B8D27_BL IAS Database has outliers
Landsat-7 ETM+ Radiometry Talk 4. LPSO Path-Processing of ETM+ Background Path-Processing Bkgds Change on Path-174 We do not know why Temperature? John Barker: 1) 2)
B3D08 Mixed Gain Background Trend Expanded Scale for High Gainfor Path-174 2004SEP21
B3D08 Mixed Gain Background Trend Expanded Scale for Low Gainfor Path-174 2004SEP21
B7D9 Mixed Gain Background Trend Expanded Scale for High Gainfor Path-174 2004SEP21
B7D9 Mixed Gain Background Trend Expanded Scale for Low Gainfor Path-174 2004SEP21
Landsat-7 ETM+ Radiometry Talk 4. LPSO Path-Processing of ETM+ Background Path-Processing (PP) Software designed To test sources of noise Before & after SLC_Off John Barker: 1) 2)
Two Spikes with IAS 500mf Background B2D12 2002NOV12 FWD (Odd) Scans, 1st larger
Spikes 3 mf wide in Background B2D12 2002NOV12 FWD (Odd) Scans, 1st higher
“Aggregate” Within-Scan Spectra used to define bDCR, DCR & aDCR regionsB2D12 2002NOV12 FWD (Odd) Scans, 1st SD larger bDCR30mf DCR 333mf aDCR250mf FWD
Two Spikes with IAS 500mf Background B2D12 2002NOV12 REV (Even) Scans, Larger comes first in time; same size as FWD
Spikes 3-5 mf wide in Background B2D12 2002NOV12 REV (Even) Scans1st in time has higher intensity (DCR On)
“Aggregate” Within-Scan Spectra used to define bDCR, DCR & aDCR regionsB2D12 2002NOV12 REV (Even) Scans, 1st SD larger aDCR30mf DCR 333mf bDCR250mf REV
Two Spikes with IAS 500mf Background B8D27 2002NOV12 FWD (Odd) Scans, 1st larger
Spikes 3-6 mf wide in Background B8D27 2002NOV12 FWD (Odd) Scans, 1st higher
“Aggregate” Within-Scan Spectra used to define bDCR, DCR & aDCR regionsB8D27 2002NOV12 FWD (Odd) Scans, 1st SD larger Coherent Noise? SLC Reset?
Two Spikes with IAS 500mf Background B8D27 2002NOV12 REV (Even) Scans, Larger comes first in time; same size as FWD
Spikes 2-6 mf wide in Background B8D27 2002NOV12 REV (Even) Scans1st in time has higher intensity (DCR On)
“Aggregate” Within-Scan Spectra used to define bDCR, DCR & aDCR regionsB8D27 2002NOV12 REV (Even) Scans, 1st SD larger Coherent Noise? SLC Reset?
Landsat-7 ETM+ Radiometry Talk 4. LPSO Path-Processing of ETM+ Background Path-Processing Tools are designed For high sensitivity To test source of change John Barker: 1) 2)
Landsat-7 ETM+ Radiometry Talk 4. LPSO Path-Processing of ETM+ Background ETM+ Forward Scan Along-Track Shutter Background B2D12 in DCR Region John Barker: 1) 2)
B2D12_BF333_DCR_251TA1 vs t_onAveraged Per-Scan BackgroundIf this is random, should TA_B be used instead of B?
ConclusionsTalk 4. LPSO Path-Processing of ETM+ Background Noise spikes occur with current 500 mf background apparently due to on/off pulse of DC Restore 333 mf DCR region appears to be noise-free John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Operational IAS Background RecommendationsTalk 4. LPSO Path-Processing of ETM+ Background Use 333 mf shutter region within DC Restore (DCR) to avoid on/off DCR spikes instead of current 500 mf region John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Bkgd Research Recommendations(1 of 2)Talk 4. LPSO Path-Processing of ETM+ Background Aggregate along-track within-scan background spectra and their variability in order to select background collect windows on the shutter that are constant. Recommend new background collect windows for IAS to avoid DC Restore (DCR) on/off spikes Cross-validate path-processing with scene-based bkgd John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Bkgd Research Recommendations(2 of 2)Talk 4. LPSO Path-Processing of ETM+ Background Use before, during and after DC Restore regions to check for possible memory effect (ME) Based on FASC collects, ME appears to be minor in reflective bands Develop filters & corrections for backgrounds so that scan values can be replaced with averages for the purpose of developing a path-processing alternative to current scene-based background (bkgd) characterization. Test for potential use of background average rather than line-by-line background John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit
Agenda of Workshop on The Art and Precision ofLandsat-7 ETM+ Radiometry • 9:00 1. Approach to On-Board Characterization of ETM+ • 10:00 2. Landsat-7 ETM+ MOC and PCD Telemetry • 11:00 3. IAS-Based IC Lamp Characterization • 12:00 Lunch • 13:30 4. Path-Processing (PP) of ETM+ Background • 14:30 5. PP-Based IC Lamp Characterization John Barker: 1) IC trend is relatively linear/stable after 2.6 y, after 4.2y 2) Principle components, graying of all bands, internal IC optics ( Dichroics or ND filters) needs to be done to agree to Lamp-2 3_need sensitivity curves on orbit