Tangent height a ura y ofSuper ondu tingSubmillimeter-WaveLimb-Emission Sounder(SMILES) on InternationalSpa e Station (ISS)O hiai Satoshi (NICT, Tokyo, Japan)Nishibori Toshiyuki (JAXA, Tsukuba, Japan)Kiku hi Ken-i hi (NICT, Tokyo, Japan)Mizobu hi Satoko (JAXA, Tsukuba, Japan)Manabe Takeshi (Osaka Pref. Univ., Japan)Mitsuda Chihiro (Fujitsu FIP, Tokyo, Japan)Philippe Baron (NICT, Tokyo, Japan)Ueno Shiro (JAXA, Tsukuba, Japan)
IGARSS 2012, Muni h, Germany, 2012/07/24
TU4.6.3
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the Super ondu ting Submillimeter-Wave Limb-Emission Sounder (SMILES)the International Spa e Station (ISS) 1 m (H)0.8 m (W)1.8 m(L)476 kg
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Contents
pp.4−13pp.14−18pp.19−25
Title:Tangent height a ura y of Super ondu ting Submillimeter-WaveLimb-Emission Sounder (SMILES) on International Spa e Station (ISS)Introdu tion of SMILES,in luding performan e results and alibration issuesISS attitudeTangent height a ura y ofthe SMILES observation
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp3/26
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp4/26
SMILES (Super ondu ting Submillimeter-Wave Limb-Emission Sounder)
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SMILES is the se ond payload from this side.
• SIS re eivers in 625 and 650 GHz bands;very high sensitivity for submillimeter-wavelimb-emission observation• Atmospheri observation on ISS:from O t. 2009 to Apr. 2010• Target spe ies:O3, HCl, ClO, HOCl, HO2, HNO3, CH3CN,and BrO;Also stratospheri wind, UTLS water vaporand i e louds.• Developed jointly by NICT and JAXA
National Institute of Informationand Communi ations Te hnology Japan Aerospa eExploration Agen y
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp5/26
SMILES Instrument
624.3-626.3 GHz 1.55-2.75 GHz
1.55-2.75 GHz
Sw
itch
Mat
rix AOS AU1
Spectrometers
CalibrationHot Load
Cold Sky Terminator
from
Atmospheric
Limb
SwitchMirror
Main Reflector
IF Amplification Section
39.2 cm x 20 cm
FSPs
11-12.2 GHz
11.8-13 GHz
11.8-13 GHz
4 K
16 K
76 K
SISMixers
JT
293 K
SMI
BBH
BBH
637.32 GHz
Submm Local Osc.
Stir
ling
Comb Generator
Do
wn
Co
nve
rter
s
Att
enu
ato
rs
Star Cameras
Data Processor & Controller
Cryostat
I/F to JEM
649.1-650.3 GHz
AOS AU2
Frequen ies :LSB : Band A: 624.26− 625.59 GHz,Band B: 625.06− 626.38 GHz,USB : Band C: 649.05− 650.38 GHzFrequen y Resolution / Bandwidth: (two AOS units)about 1.1 MHz / 1.3 GHz
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp6/26
Antenna and Opti sLocal Oscillator(637.32 GHz)
fromAntenna
ColdTermination
Sideband SeparatorElevation steerable antennaAperture: 392 mm× 200 mmBeam widths (�3 dB): 0.089◦ × 0.173◦Height resolution at tangent point: 3.2 kmSIS re eivers are lo ated belowthe sideband separatorSubmillimeter Opti sin ludes sideband separator, lo al diplexer.The opti s is installed in a shielded box.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp7/26
SubMM Re eiver and Cryo ooler
Inside of Cryostat Compressors
Cryostat
Optics incl. SSB separtor, submm-LO
4 K
20 K
100 K
HEMT amps.
SIS mixers
SIS mixer operated at 4.3 K
Submm Re eiver (Super ondu ting mixer)Two re eivers in 624− 626 and 649− 650 GHzSystem noise temperature is 315−320 K in SSB operationCryo ooler (Joule-Thomson y le and Stirling oolers)Cooling Capa ity : 20 mW � 4.3 KPower Consumption : 120 W nominal � BOLMass : 82 kg (in l. Cryostat: 24 kg)
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp8/26
Re eiver Performan e
200
250
300
350
400
450
500
624.4 624.6 624.8 625 625.2 625.4
TS
YS (
SS
B)
[K]
Frequency [GHz]
Band A (LSB receiver)
Maximum in Orbit
Minimum in Orbit
Prelaunch Test
200
250
300
350
400
450
500
625.2 625.4 625.6 625.8 626 626.2
TS
YS (
SS
B)
[K]
Frequency [GHz]
Band B (LSB receiver)
200
250
300
350
400
450
500
649.2 649.4 649.6 649.8 650 650.2
TS
YS (
SS
B)
[K]
Frequency [GHz]
Band C (USB receiver)
1e-07
1e-06
1e-05
1e-04
0.001
0.001 0.01 0.1 1
Pow
er S
pect
ral D
ensi
ty [H
z-1]
Frequency [Hz]
Band B (626.06 GHz)200911101346-200911121340
1.089 x 10-8 (1/f)1.592
ch.1296
B= 8 MHz
B= 64 MHz
The SMILES SIS re eiver shows very high sensitivity,meeting requirement with a margin.The noise level is one order of magnitude below the onventional submillimeter sounder in spa e.The stability time of the re eiver is about 8 s in spa e.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp9/26
Antenna S an Pattern
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0
5000
10000
15000
20000
25000
30000
35000
40000
45000
50000
1.6 1.8 2.0 2.2 2.4 2.6 2.8
Det
ecte
d P
ow
er
AOS Frequency [GHz]
Hot Calibration
Cold Calibration
Limb Observation
Tan
gent
Hei
ght
0 km
90 km
190 km
Hot CalibrationFreq. Calib.
53 sTyp
ical
Det
ecte
d P
ower
Cold Calibration
Limb Scanning
0
0.1
0.2
0.3
0.4
0.5
625.2 625.4 625.6 625.8 626 626.2
∆T [
K]
Frequency [GHz]
Band B AU2
Single channel with drift
Single channel without drift
64-MHz resolution with drift
SMILES repeats limb s annig, old alib.,freq. alib., and hot alib. every 53 s(horizontal sampling period: 360 km)Considerable long alibration period (53 s)has no impa t on spe tral ∆T (< 0.42 K).∆T for ontinuum signal is < 0.27 K.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp10/26
Example of Observed Spe tra
0
50
100
150
200
250
Lim
b B
right
ness
[K
]
SMILES band C, 2010/01/28 09:44, 45.6E 65.4N, SZA=83.8o
ClO10.1 km12.2 km14.3 km
16.4 km
18.4 km
20.5 km
22.6 km24.6 km26.6 km
-2 0 2 4 6 8 10
649.2 649.4 649.6 649.8 650.0 650.2 650.4
Frequency [GHz]
18OOO
HO2
17OOO 28.6 km
30.6 km
44.7 km
0
50
100
150
200
250
Lim
b B
right
ness
[K
]
SMILES band B, 2010/01/27 09:21, 44.1E 64.9N, SZA=83.3o
O3 HCl
11.5 km
13.6 km
15.6 km
17.7 km
19.8 km21.8 km23.9 km
-2 0 2 4 6 8 10
625.2 625.4 625.6 625.8 626.0 626.2
Frequency [GHz]
18OOO O18OO
30.0 km
34.0 km
44.1 km
0
50
100
150
200
250
Lim
b B
right
ness
[K
]
SMILES band A, 2010/01/28 09:44, 45.6E 65.4N, SZA=83.8o
O3H37Cl
10.1 km12.2 km
14.3 km
16.4 km
18.4 km
20.5 km
22.6 km24.6 km
-2 0 2 4 6 8 10
624.4 624.6 624.8 625.0 625.2 625.4 625.6
Frequency [GHz]
O3,v1,3 O3,v2
28.6 km
30.6 km
44.7 km
Every 53 s, two of these three sets oflimb spe tra were observed.The spe tra have low ∆T and stablespe tral baselines.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp11/26
Calibration of Observed Spe tra• Brightness intensity alibration
• Frequen y alibration
• Field-of-view alibration
T∆
f∆
z∆ISS
• Intensity-s ale alibration• Gain-nonlinearity orre tion• Frequen y-s ale alibration• Filter response pattern measurement• Tangent-height alibration• Beam-pattern measurement
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp12/26
Calibration of Observed Spe tra• Brightness intensity alibration
• Frequen y alibration
• Field-of-view alibration
T∆
f∆
z∆ISS
• Intensity-s ale alibration• Gain-nonlinearity orre tion• Frequen y-s ale alibration• Filter response pattern measurement• Tangent-height alibration• Beam-pattern measurement
(dis ussed in profile-validataion papers)→ IEEE JSTARS, 5(3), 2012.
See a Wednesday poster WEP.P.363.→ IEEE JSTARS, 5(3), 2012.
→ IEEE TAP, 60(8), 2012.Today's topi s
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp13/26
Calibration of Observed Spe tra• Brightness intensity alibration
• Frequen y alibration
• Field-of-view alibration
T∆
f∆
z∆ISS
• Intensity-s ale alibration
• Frequen y-s ale alibration
• Tangent-height alibration
WEP.P.363.
Today's topi s
Brightness resolution : <0.42 K (1.1 MHz resol.)→ Intensity s ale <1 % (∼2 K)Frequen y resolution : 1.1 MHz→ Frequen y s ale <10 kHz (relative)→ Frequen y s ale <100 kHz (absolute)Height resolution : ∼3 km→ Height s ale <50 m (relative)
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp14/26
ISS Attitude
2000 km
Tangent point
ISS Altitude: 333 - 370 km
SMILES observes limb emission in a tangent height rangebetween ∼0 and 100 km with a step of about 2 km.
We need to know the ISS attitude with enough pre isionfor the limb observation.Tangent-height pre ision ∼ 50 m→ Pointing pre ision needs to be less than 0.0014◦ (5 ar se )
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp15/26
Typi al ISS Attitude ISS orbit
Tangent point65 No
38 So
-5.6
-5.2
-4.8
-4.4
-1.2
-0.8
-0.4
0.0
0.4
15:00 15:15 15:30 15:45 16:00 16:15 16:30 16:45 17:00 17:15 17:30 17:45 18:00
Attitude by ISS GN and C, 2010/01/25
ISS
Att
itu
de
[d
eg]
Roll
Pitch
Yaw
3 hoursOrbit period length
1◦
ISS ir ulates around the Earth with a periodof about 91 min.The attitude varies almost periodi ally, butthe orbit-by-orbit variation is unpredi table.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp16/26
Bending of ISS Stru ture
ISS GN&C
SMILESLimb viewing Photo ourtesyof
NASA
Mutual movement between SMILES and the ISS main body dependson the dire tion toward the sun. SMILES moves slowly relativeto the ISS main body with anamplitude of about 0.05◦ or less.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp17/26
Vibration of ISS Stru tureISS GN&C
MAXI
SMILES Photo ourtesyofNASA
-1.184
-1.183
-1.182
-1.181
-1.180
-1.179
-1.178
-1.177
-1.176
-1.175
-1.174
16:16:00 16:16:30 16:17:00 16:17:30 16:18:00 16:18:30 16:19:00
ISS
Pit
ch [
deg
]
ISS attitude, 2010/01/25
Attitude by MAXI/R
LG
Attitude by ISS GN and C
In short time s ale, the attitude aroundSMILES moves by about 0.003◦ (peak-to-peak) o asionally.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp18/26
Vibration of ISS Stru ture
2010/01/25 (GMT)
Fre
qu
ency
[H
z]
Vibration between MAXI/RLG and ISS/GNC [deg]
00:00 04:00 08:00 12:00 16:00 20:00 00:00
0.1
1
0.0000
0.0001
0.0002
0.0003
0.0004
0.0005
0.0006
0.0007
0.0008
0.01
A remarkable vibration around 0.25 − 0.3 Hz isobserved from 7:00 to 23:00 (GMT).This vibration is known as a resonant frequen y ofISS ex ited by a tivity of astronauts.
Color spe trogram of angular attitude differen e between ISS GN&C and MAXI.The olored value is an integration of vibration amplitude density over a third o tave.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp19/26
Tangent Height Calibration
0
20
40
60
80
100
0 50 100 150 200 250
Tan
gent
Hei
ght [
km]
Limb Brightness [K]
• The tangent height an be retrievedfrom the spe tra.• The tangent height an be derivedfrom geometri al data.We dis uss here the geometri alderivation.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp20/26
Geometri al Tangent Height Derivation
(1)
(3)
(4)
(2)
Tangent Height
Error sour es of geometri ally derived tangent height:(1) Offset of the submillimeter beam dire tion from a me hani al axis(stable systemati error)(2) Error in an en oder of the antenna elevation angle (∼0.0008◦)(3) Error of the position of ISS (basi ally negligible, ex ept the JEM's error)(4) Error of the attitude in inertial spa e
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp21/26
SMILES Star Sensor
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-0.35
-0.3
-0.25
-0.2
-0.15
-0.1
-0.05
0
0.05
16:46 16:48 16:50 16:52 16:54 16:56 16:58
Atti
tude
rel
ativ
e to
ISS
[deg
]
SMILES star sensor attitude, 2010/02/23
Cross axis (nadir)
Cross axis (orbit perp.)
Twist angle about boresight
SMILES dete ts the attitude with a star amera.
Bore dire tion of the star amera Submillimeter beam dire tionThe error in the star sensor of an axis around the amera bore (r.m.s. 0.017◦) propagates to the tangentheight error (r.m.s. 0.01◦ in elevation angle).
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp22/26
MAXI Ring Laser Gyros ope
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6
������
SMILESMAXI
The ring laser gyros ope (RLG) installed onthe Monitor of All-sky X-ray Image (MAXI)is used to determine the SMILES attitude.The tangent height is derived from an attitude that is based on the RLG dataand averagely aligned with the SMILES star-sensor attitude.RLG has an attitude pre ision ofabout 0.001◦ (rms).
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp23/26
Attitude based on the RLG Data
-0.160-0.150-0.140-0.130-0.120-0.110-0.100-0.090
16:12 16:13 16:14 16:15 16:16 16:17 16:18 16:19 16:20 16:21 16:222010/01/25 16:11:57 - 16:22:33
Z-a
xis
(ro
ll) [
deg
]
σ(starcamera-RLG)= 47.81’’ σ(RLG-ISS)= 15.56’’
-0.066-0.064-0.062-0.060-0.058-0.056-0.054
Y-a
xis
(-p
itch
) [d
eg]
σ(starcamera-RLG)= 2.47’’ σ(RLG-ISS)= 5.03’’-0.136-0.134-0.132-0.130-0.128-0.126-0.124
Attitude Differences
X-a
xis
(yaw
) [d
eg]
σ(starcamera-RLG)= 4.24’’ σ(RLG-ISS)= 10.00’’
SMILES/star camera - ISS/GNCMAXI/RLG - ISS/GNC
From the ring laser gyros ope (RLG) data, an attitude data is estimated so as to agreewith the star-sensor attitude averaged for SMILES s an period (53 s) in X and Y axes,and for longer time s ale (±3 min.) in Z axis.This alignment estimation gives an error of about 0.003◦.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp24/26
Tangent Height Profile of a S an
-300
-200
-100
0
100
200
300
0 5 10 15 20 25 30 35
Time from the beginning of the scan [s]
Dif
fere
nce
fro
m t
he
qu
asi-
linea
r sc
an p
atte
rn [
m]
SMILES/star cameraISS/GNC
MAXI/RLG
0
50
100
150
200 SMILES scan at 2010/01/25 05:37:48
Tan
gen
t A
ltit
ud
e [k
m]
SMILES/star cameraISS/GNC
MAXI/RLG
-400
-300
-200
-100
0
100
200
0 5 10 15 20 25 30 35
Time from the beginning of the scan [s]
Dif
fere
nce
fro
m t
he
qu
asi-
linea
r sc
an p
atte
rn [
m]
SMILES/star cameraISS/GNC
MAXI/RLG
0
50
100
150
200 SMILES scan at 2010/01/25 16:17:22
Tan
gen
t A
ltit
ud
e [k
m]
SMILES/star cameraISS/GNC
MAXI/RLG
Nighttime Daytime
0.005◦
2◦
Tangent height is estimated from SMILES star sensor, ISS GN&C, and MAXI RLG.Offset (∼0.1◦) in ISS/GN&C tangent height is removed in the figures.
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp25/26
Tangent Height Profile of a S anThe standard deviation of the tangent-height mean offset,whi h is al ulated by retrieval pro ess from spe tra of a s an,is 0.14 km (0.0038◦ in elevation angle).That is onsistent with a root sum-square of:RLG-attitude standard deviation 0.001◦Error in estimation of the initial orientation for RLG 0.003◦En oder error of the antenna elevation angle 0.0008◦Error in al ulation of the tangent-height mean offset from spe tra 0.002◦The initial-orientation error (0.003◦) is the error in aligningthe RLG data with the SMILES star-sensor attitude.It will be redu ed in future improvement of the algorithm.
The relative error of the tangent heights in a s anis about 46 m (0.0013◦)Photo ourtesyofNASA
IGARSS 2012 Tangent height a ura y of SMILES on ISS, o hiai�ni t.go.jp26/26
Summary• SMILES performan e and alibration
• Atmospheri limb was su essfully observed for 6 month withvery low noise and almost perfe t baseline feature• The spe tra are well- alibrated in intensity and frequen y s ales.
• ISS attitude• SMILES moves slowly relative to the ISS main body with 0.1◦ p-p.• JEM o asionally has a vibration of 0.003◦ p-p with a frequen yof about 0.25 Hz.
• SMILES tangent-height a ura y• The data from the ring laser gyro. of MAXI is used to al ulatetangent heights.• The error of the tangent height is about 46 m (0.0013◦) in a s an.• The standard deviation of the tangent-height offset error of ea hs an is less than 140 m (0.0038◦).
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