SGLI HARDWARE
STATUS
January 16, 2014
Joint PI Workshop @ TKP Takebashi
Kazuhiro TANAKA
Sub Manager
GCOM Project Team/JAXA
http://suzaku.eorc.jaxa.jp/GCOM_C/index_j.html

Contents
 GCOM mission and GCOM-C1 satellite Current Status SGLI Peformance Visible and Near infrared Radiometer (VNR)
 Infrared Scanning Radiometer (IRS) Stary Light Correction
 Conclusion

SGLI Hardware Status at GCOM PI Workshop Jan. 16 20142

Global Change Observation Mission(GCOM) Global observation satellite system as JAXA’s GEOSS contribution.
 2 satellite series for 5 years, total 13 years observation.
 GCOM-W Microwave radiometric observation for WATERCYCLE using AMSR2 (AMSR-E follow on)
 GCOM-C
Optical multi-channel observation for RADIATIONBUDGET and CARBON CYCLE using SGLI (GLI follow on)
GCOM-C(CLIMATE)

GCOM-W(WATER)AMSR2GCOM-W1 “SHIZUKU”
was launched on May 18,
2012.

SensorAdvanced Microwave Radiometer 2(AMSR2)
Passive Microwave Observation
Water vapor, soil moisture etc

SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

GCOM-C1
is scheduled for launchin JFY2016.

Sensor

SGLISecond Generation Global Imager(SGLI)
Optical Observation 380nm – 12 micron
Cloud, Aerosol, Vegetation, Chrolophl etc

3Second generation Global Imager (SGLI)
on GCOM-C1 satellite
SGLI VNR
ELU

SGLI IRS
ELU+Y
deep
space+X
flightdirection+ Z earth

SGLI VNR
SRU

SGLI IRS
SRU
Mission Life> 5 years

Solar Paddle> 4000w （End of Life）

Mass

about 2,000kg

SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

SGLI
VNR
IRS
SRU
ELU

Second Generation Global Imager
Visible and Near Infrared Radiometer
Infrared Scanning Radiometer
Scanning Radiometer Unit
Electronic Unit

4

Current Status Critical Design Review (CDR) of SGLI sensor andGCOM-C1 satellite was held in 2013.
 The flight model (PFM) manufacturing was approved.
 The manufacturing of SGLI key flight parts, such as
optics, filters, detectors or coolers, is almost finished andunder the final inspection for the components assemblyand tests.
 SRU sensor system integration is planned in the middleof 2014. The sensor level pre-flight tests including both
optical performance tests and the environmental tests
will be done.
 Satellite level test will start in 2015 and planned forlaunch in JFY 2016.
SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

5

SGLI Performance• The SGLI features are 250m (VNR-NP, SW3 & TIR) spatial resolution andpolarization/along-track slant view channels (VNR-PL), which will improve land,
250m over the Land or coastal
coastal, and aerosol observations.
GCOM-C SGLI characteristics
Sun-synchronousOrbit(descending local time: 10:30)
Altitude 798km, Inclination 98.6deg
Mission Life 5 years (3 satellites; total 13 years)
Push-broom electric scan (VNR)
Scan
Wisk-broom mechanical scan (IRS)
1150km cross track (VNR: VN & P)
Scan width
1400km cross track (IRS: SW & T)
Digitalization 12bit
Multi-angle
Polarization 3 polarization angles for Pobs. for674nm andAlong track Nadir for VN, SW and T,
869nm
direction+45 deg and -45 deg for P

On-board
calibration

VN: Solar diffuser, LED, Lunar cal
maneuvers, and dark current bymasked pixels and nighttime obs.
SW: Solar diffuser, LED, Lunar, and darkcurrent by deep space window
T: Black body and dark current by deep
space window

area, and 1km over offshore
SGLI channels
λ∆λ
Lstd
Lmax
IFOV
NP,PL,SWI:
NP, PL, SWI:
CH NP, PL, SWI: nm
SNR at Lstd
W/m2/sr/µmm
T: µm
T: NE∆T
T: Kelvin
VN1
380
1060
210
250
250
VN2412
1075
250
400
250
VN34431064400
300
250
VN44901053120400
250
VN55302041350250
250
VN6565
20
33
90
400
250
VN7673.5202362400
250
VN8673.52025210250
250
250/1000
VN9763
12403501200
VN10 868.5
20830400
250
VN11 868.52030300200250
PL1673.52025250250
1000
PL2868.52030300
250
1000
SW110502057248500
1000
SW21380
208103150
1000
SW31630200
35057250
SW4221050
1.920211
1000
T1
10.8
0.7
300
340
0.2
250/1000
T2
12.0
0.7
300
340
0.2
250/1000
TIR : 500m resolution is also used.

SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

6

Visible and Near infrared radiometer(SGLI-VNR)
VNR-SRU••

Earth

Diffuser stowed
PL NadirEarthFlightdirection

VNR-SRU inside••Diffuser deployed
PL Backward
FlightDirection1.3m
About 290kg
400Wmax

1.7m

SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

Engineering model of SGLI-VNR
for thermal vaccumm test
configuration

7

VNR optics
 Wide FOV (NP 24deg, PL55deg) optics are in themanufacturing phase.
 1st NP optics test wascompleted and shipped in lastDecember.
 The other 4 optics are underthe test.
 Total 5 optics will be
integrated in VNR.

flightmodel

VNR optics
for Polarized Observation (PL)flightmodel

NP telescope
Obs.
LightSGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

VNR opticsfor Non-polarized Observation (NP)8

VNR focal plane assembly (FPA)
 11line CCD is ready.

11 line Band Pass Filter

flightmodel 11line NP filter is under thefinal alignment activity forthe shipment.
 Spectral performancerequirement for the filter iscomplied.

 FPA assembly with CCD

and filters starts in Jan.
2014.
 The optics and FPA will beassembled for thetelescope.
SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

11 line CCD

flightmodel

Focal Plane
Assembly9

VNR spectral performance(filter only) Because VNR is pushbroom type wide FOV sensor with 11channels, the very narrow and long filter (1mm x 100mm) isnecessary.
 In order to minimize the coating locality, special coating
facility is used.
 Precise locality measurement and analysis is ongoing.
780

VN9(26-2053)No.7 - NP-L

VN9(26-2053)No.8 - NP-N

VN9(26-2053)No.9 - NP-R

775

[nm]

770765760755※tentative analysis

750

SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

10

VNR spectral performance(filter only, tentative)
VN1-No.2 NP-L(min)VN2-No.6 NP-L(min)VN3-No.5 NP-L(max)VN4-No.4 NP-L(max)

VN5-No.8 NP-L(max)

VN6-No.6 NP-L(min)VN1-No.2 NP-L(max)

VN2-No.6 NP-L(max)

VN3-No.5 NP-L(min)VN4-No.4 NP-L(min)VN5-No.8 NP-L(min)VN6-No.6 NP-L(max)

360 370 380 390 400

395 405 415 425 435

425 435 445 455 465

VN1-No.3 NP-N(min)VN2-No.8 NP-N(min)VN3-No.6 NP-N(min)VN4-No.7 NP-N(max)

VN5-No.9 NP-N(max)

VN6-No.7 NP-N(min)VN1-No.3 NP-N(max)

VN2-No.8 NP-N(max)

VN3-No.6 NP-N(max)

VN4-No.7 NP-N(min)VN5-No.9 NP-N(min)VN6-No.7 NP-N(max)

360 370 380 390 400

395 405 415 425 435

425 435 445 455 465

470 480 490 500 510

VN1-No.4 NP-R(min)VN2-No.9 NP-R(min)VN3-No.7 NP-R(min)VN4-No.8 NP-R(max)

VN5-No.10 NP-R(max)

VN6-No.8 NP-R(min)VN1-No.4 NP-R(max)

VN2-No.9 NP-R(max)

VN3-No.7 NP-R(max)

VN4-No.8 NP-R(min)VN5-No.10 NP-R(min)VN6-No.8 NP-R(max)

360 370 380 390 400

395 405 415 425 435

425 435 445 455 465

470 480 490 500 510

NP(LEFT)
475

485

495

505

500

520

540

560

540

560

580

600

NP(NADIR)
500

520

540560

540

560

580

600

NP(RIGHT)
500

520

540

560

540

560

580

600

Note : Not all optical transmittance is considered in this calculation, such as CCD response, optics andrejection filters. The spectral shift due to the incident angle for NP filters should also be considered. The
further analysis is ongoing.
11
SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

VNR spectral performance(filter only, tentative)
VN7-No.6 NP-L(max)

VN8-No.9 NP-L(max)

VN9-No.7 NP-L(min)VN10-No.8 NP-L(max)VN11-No.12 NP-L(max)

VN7-No.6 NP-L(min)VN8-No.9 NP-L(min)VN9-No.7 NP-L(max)

VN10-No.8 NP-L(min)VN11-No.12 NP-L(min)PL-1

NP(LEFT)

PL-1
645

665

685

705

645

665

685

705

740

760

780

800

840

860

880

900

VN7-No.7 NP-N(max)

VN8-No.10 NP-N(max)

VN9-No.8 NP-N(min)VN10-No.9 NP-N(max)

VN7-No.7 NP-N(min)VN8-No.10 NP-N(min)VN9-No.8 NP-N(max)

VN10-No.9 NP-N(min)840

860

880

900

VN11-No.13 NP-N(max)VN11-No.13 NP-N(min)

645

665

685

705

PL-2NP(NADIR)

PL-2
645

665

685

705

VN7-No.8 NP-R(max)
VN7-No.8 NP-R(min)

645

665

685

705

740

VN8-No.11 NP-R(max)
VN8-No.11 NP-R(min)

760

780

800

840

860

880

900

840

860

880

900

VN9-No.9 NP-R(max)

VN10-No.10 NP-R(max)VN11-No.14 NP-R(max)

VN9-No.9 NP-R(min)VN10-No.10 NP-R(min)VN11-No.14 NP-R(min)

840

860

880

900

NP
(RIGHT)
645

665

685

705

645

665

685

705

740

760

780

800

840860880

900

840860880

900Note : Not all optical transmittance is considered in this calculation, such as CCD response, optics andrejection filters. The spectral shift due to the incident angle for NP filters should also be considered. The
further analysis is ongoing.
12SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

Infrared Scanning Radiometer(SGLI-IRS)
EarthEarth

Deep space

Flightdirection
FlightDirection

OBS Light

SWI-DET

SCAN
MOTOR

Engineering model of SGLI-IRS
for vibration test configuration

OpticalBench

SterlingCoolerBLACKBODY

TIR-DETSGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

IRS telescope(Flight Model)
13IRS scanning mechanism
 Scanning mirror is ready.
 Slotless AC Servo Motor isready.
 The integration of scannig
mechanism and rotation control
adjustments are ongoing.
25000

Resolver Calibration Accuracy

Histgram

20000

Scanning
Mirror (flight model)
Scanning Mechanism(flight model)

σ=0.02pixel

15000
10000
5000

0.147

0.124

0.101

0.078

0.054

0.031

0.008

-0.016-0.039-0.062-0.085-0.109-0.132-0.1550[250m pixel]

SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

14

SWI focal plane assembly(SWI-DET) InGaAs type SWI PD arrayis ready.
 SWI 4band filter is ready.

SWI4Band Filters

 Spectral performancerequirement is complied.

 The detector array iscooled at -30deg to reducethe dark signal.
 The integration to thedetector package is almostdone.
 The pre-shipment acceptance

FlightModel
Window
4BAND FILTER

4BAND PD ARRAY

Peltier Cooler

test is ongoing.
SGLI Hardware Status at GCOM PI Workshop Jan. 16 201415

TIR focal plane assembly(TIR-DET)
 PV type MCT detector andFlightModelfilter was alreadyintegrated in the LWIRD
package and shipped.

CryogenicDewar
Cold Head Spectral performancerequirement for the LWIRD iscomplied.
Balancer The cooler assembly forthe 55K is under the final
performance test.
 LWIRD will be integrated in
the cryogenic dewar inFebruary, 2014.
SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

FlightModel
Compressor

Long Wave
Infrared Dector(LWIRD)

Cooler Assembly16IRS spectral performance(tentative)
 Because IRS is wiskbroom type sensor, filter size is muchsmaller than VNR. Coating and measurement facility tocover the IR region is required. Detector temperature
should also be considered.

SW1

900

1000

1100[nm]

1200

1450

1550

1650
[nm]

1750

SW2

1200

1300

1400
[nm]

1500

TIR-1A
TIR-1B

SW3

9.5

10.0

10.5
11.0[μm]

2100

2200
[nm]

2300

2400

12.0

TIR-2A
TIR-2B

SW4

2000

11.5

10.5

11.0

11.5

12.0
[μm]

12.5

13.0

13.5

Note : Not all optical transmittance is considered in this calculation, such as scan mirror and optics,
although the above response is dominant for total IRS response. The further analysis is ongoing.

SGLI Hardware Status at GCOM PI Workshop Jan. 16 201417

Stray Light Correction
 Stray light phenomena is observed during EM opticalperformance tests (VNR and SWI bands).
 Scattering and diffraction within focal plane assembly is
identified for the root cause of this phenomena.
 Deconvolution technique using the transfer function isapplied in L1B processing system to meet therequirements (2% of Lstd at 2km from the bright lightedge), similar to MERIS, OLCI and POLDER algorithm.
 VNR geometrical parallax effects is considered for thecorrection. The saturated radiance in high gain channel
is corrected using low gain channel outputs.
 SWI mechanical scanning effects is considered.
SGLI Hardware Status at GCOM PI Workshop Jan. 16 201418

Stray Light Simulation
Original
MODIS
CHLA

CHLAwith Stray
Light

ΔCHLA

20（Stray light）

Effects ofStray Light
迷光により、クロロフィル計算量が減少

18
16

CHLA [mg/m^3]

14

迷光なし

12迷光あり（Δr）

10迷光あり（Δr+Δra）

crosssection

864
20

CHLA
after
correction

ΔCHLA

450

20（Correction Err）

440

430

420
pixel

410

400

390

400

390

Effects ofCorrection

迷光補正により、クロロフィル計算量が改善

1816CHLA [mg/m^3]

14Note:The purpose of thiswork is for sensitivity
analysis only
MYD021KM.A2012238.0420.005.2012238172859
SGLI Hardware Status at GCOM PI Workshop Jan. 16 2014

迷光なし
12迷光あり（Δr）

10迷光あり（Δr+Δra）

8
6
4
20450

440

430

420
pixel

410

[line = 1661 - 1760 pixel = 391-490] Aqua MODIS 1km resolution

19Conclusion
 SGLI flight model manufacturing is ongoing.
 Key flight parts test meets the requirements.
 Sensor integration & test will be started within

this year.
 Stray light correction is implemented in theground L1B processing system.
 Target launch of GCOM-C1 is JFY2016.

SGLI Hardware Status at GCOM PI Workshop Jan. 16 201420