Transcript Characteristics of GOES Sounder Detectors

Characteristics of GOES-13
Sounder IR Detectors
Dejiang Han
December 22, 2006
Comparisons of Spectral Response Functions for
GOES-12 and GOES-13 Sounders
(Channels 1 – 9)
GOES-12
GOES-13
Comparisons of Spectral Response Functions for
GOES-12 and GOES-13 Sounders
(Channels 10 – 18)
GOES-12
GOES-13
Striping Due to SRF Differences (Channels 1 – 9)
GOES-12
GOES-13
ITT provides temperature-to-radiance conversion coefficients, which are determined with the detector
spectral response functions. The coefficients are used in the GOES SPS data processing. Plots presented on
this page and next show the GVAR count differences within a channel. The difference for each detector is
defined as Value (single detector) – Mean Value (all detectors). In the course of Temperature→Radiance
→GVAR counts, no detector saturation is taken into account. Symbols used in the plots on this page and
those following:
+ Detector 1
* Detector 2
◊ Detector 3∆ Detector 4
 For channel 7 of both GOES-12 and GOES-13, detector 4 differs from the other three.
Striping Due to SRF Difference (Channels 10 – 18)
GOES-12
GOES-13
 For both GOES-12 and GOES-13, channels 11 and 12 have one detector behaving somehow differently
from the other three.
GVAR Counts Profiles of GOES-13 Sounder CH 1 – 9
During the ITT’s pre-launch spacecraft T/V tests, the Sounder was directed to view a target, whose
temperature was controlled at 295 K. The T/V tests were recorded on a tape, which was played back and
processed by the GOES SPS. The above profiles are organized channel by channel. Line types used for each
channel are
solid: Detector 1
Dotted: detector 2
dashed: Detector 3
dash dotted: Detector 4
(cont’d)
GVAR Counts Profiles of GOES-13 Sounder CH 10 – 18
 Channels 1 - 3, and 12 are saturated.
 Channels 7 – 9, 11, and 13 – 15 appear to have one detector whose GVAR count profile is different from
the other three.
 For GOES-13 Channel 7, in particular, detector 4 seems to stand alone. This is consistent with the
spectral response function profiles for the channel. In the GOES-13 NOAA Science Tests, however, the
reported detector is detector 3.
Temperature Differences of GOES-13 Sounder CH 1 – 18
Temperature differences observed for each channel of GOES-13 Sounder
during the ITT’s pre-launch spacecraft T/V tests.
GOES-13 Sounder Mean and Standard Deviation of
Retrieved Temperatures over a Controlled Target
Mean
282.128
281.980
291.590
294.324
294.345
294.384
294.550
294.336
294.739
294.933
294.970
291.344
295.131
295.090
295.117
295.184
295.189
295.233
282.118
281.974
291.592
294.303
294.298
294.391
294.499
294.311
294.495
295.024
295.080
291.295
295.034
295.000
294.991
295.154
295.145
295.212
282.136
281.980
291.590
294.309
294.312
294.369
294.444
294.435
294.551
294.972
294.950
291.339
295.087
295.073
295.101
295.181
295.115
295.271
282.088
281.961
291.584
294.313
294.278
294.336
294.820
294.532
294.540
294.900
294.954
291.317
295.102
295.061
295.084
295.166
295.146
295.223
STD
1.04609e-11
3.29746e-12
1.07452e-11
0.0922671
0.102328
0.0536734
0.0342686
0.0452732
0.0528262
0.0589241
0.0409950
3.41116e-12
0.0468195
0.0430578
0.0420997
0.0485417
0.0487201
0.0442136
9.09644e-12
1.37015e-11
1.47249e-11
0.0961847
0.0922615
0.0511453
0.0419468
0.0409233
0.0480543
0.0420942
0.0342842
5.40101e-12
0.0542628
0.0574043
0.0487656
0.0518586
0.0591520
0.0476579
(Vertical: Channels; Horizontal: Detectors)
2.72893e-12 1.17117e-11
5.79898e-12 5.11675e-12
2.22863e-11 1.88183e-11
0.0993450 0.106696
0.102111 0.0908641
0.0561833 0.0395547
0.0433724 0.0390956
0.0338494 0.0615479
0.0398897 0.0583666
0.0457885 0.0622064
0.0342714 0.0465201
1.47817e-12 5.34416e-12
0.0616064 0.0502991
0.0412791 0.0520371
0.0348367 0.0526656
0.0263090 0.0454805
0.0535933 0.0597365
0.0375237 0.0406419