STAR Calibration Support for GOES Post Launch Test (PLT)

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STAR Calibration Support forGOES Post Launch
Test (PLT)

• X. Wu F. Yu
• NOAA/NESDIS/STAR/SPB ERT _at_ NOAA

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PLT Overview

• GOES PLT is similar to POES OV in many ways
• Longer, more complicated spacecraft maneuver
• Engineering Test
• Functionality of component and system
  (instrument)
• Science Test
• Products generation from instrument measurements
• Radiance quality can be part of either, but has
  been primarily part of the Science Test.

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PLT History (Science Test)

• GOES-8 (1994)
• 1st of its kind learn to make the best use of
  the data
• Radiance is validated (quite substantially), but
  little beyond
• GOES-9 (1995)
• Still not formal, if any.
• GOES-10 (1997)
• Solar panel deployment led to yaw flip
• Science Test in April 1998 to make sure its
  compatible with GOES-8/9
• 1st 1-min rapid scan.
• Goes-11/12 (2000/2001)
• Formal and routine
• GOES-13 (2006)
• Significant change in hardware more
  sophisticated Science Test

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PLT Structure

• Engineering test has always been led by NASA
• Science Test was earlier led by CIMSS and later
  co-led with OPDB or CIRA.
• Calibration support
• STAR personnel detailed at SOCC
• With contractor support at SOCC
• Engineering Test
• Oversee the Implementation of CPIDS (examples).
• Supply certain tests (example)
• Science Test
• Diagnose and correct for operational and
  calibration anomalies (examples)

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Calibration Database Before/During PLT

• Specify and verify
• Coefficients and limits
• Changes (e.g., BB dwell)
• Generate some, e.g., band correction, scan mirror
  emissivity
• OGE Compatibility Test
• Unlike POES, GVAR is not Level 1b (in its
  traditional definition)
• Need to test calibration and geo-location

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Test Description for PLT

• TEST NUMBER IC115
• TEST NAME Benefits of Imager Extended Blackbody
  Dwell
• TEST ENGINEER Angel Butts
• TEST TYPE Characterization
• TEST DURATION N/A
• SPECIFICATION REFERENCES
• GOES-NOPQ CCR 4233 Rev. (8/22/00) Increase SN08
  Imager Black Body Dwell Time.
• GOES-NOPQ CCR 4233 Rev. B (2/27/01) Imager
  Blackbody Dwell Modifications and Miscellaneous
  Cleanup of the GOES NOPQ Imager and Sounder ICDs.
  
• OBJECTIVES
• To quantify the reduction in the variability in
  the means of the blackbody counts, the
  calibration slopes, and the frame-mean striping
  resulting from the increase in blackbody dwell
  time from 0.2s to 2.0s.
• DESCRIPTION
• 1. Data collected during 24 hours of successive
  blackbody events will be processed in parallel in
  two MSPSs. At each blackbody event, each MSPS
  routinely computes the means and standard
  deviations (in units of 10-bit digital counts) of
  the sequence of blackbody samples in each IR
  channel. In these computations, at each event one
  MSPS will use only the first 1000 blackbody
  samples, while the second MSPS will use the
  entire nominally 10,000 samples. We will use
  the means and standard deviations of the
  blackbody count levels, routinely produced by the
  MSPSs, to compute the standard errors of the
  means for each channel for each blackbody event.
  The standard errors from the two MSPSs will be
  compared. (If the distribution of blackbody data
  were close to normal, their ratio would be
  approximately ?10.) Also, the standard
  deviations (in counts) will be converted, through
  the calibration, to units of temperature and
  compared with the noises computed from
  thermal/vacuum tests and the noises computed in
  PLT IS004--Imager IR Channel Noise Equivalent
  Temperature Differences. The S.D.s from the 1000
  and the 10,000 samples should be nearly the same,
  both of them should be about the same as the
  S.D.s from the other tests, and all of them
  should meet spec.

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Calibration Support During/After PLT

• Operational anomalies confirm and diagnose
• GOES-13 Sounder visible channel boost
• GOES-14 cal/nav coeff., buffer overflow, Imager
  Ch6 det ID
• Calibration Anomalies things were more or less
  complicated
• Scan mirror emissivity
• Midnight Blackbody Calibration Correction
• Imager visible channel normalization
• Radiance validation accuracy precision
  GEO-GEO GEO-LEO vis IR, imgr sndr
• Co-registration
• Stray light
• Sounder striping

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Preliminary http//www.star.nesdis.noaa.gov/smcd/
spb/fwu/homepage/GSICS_GOES14_AIRS_IASI.php
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Issues

• Need data during PLT
• Both in real time and archived
• Better for GOES-14, but far from ideal
• Even available, GVAR is not Level 1b
• Often a limiting factor for detailed
  investigations
• Need more dedication