JEM-SMILES Instrumental Capabilities Junji INATANI Space Utilization Research Program NASDA Feb. 21, 2001, Kyoto JEM-SMILES

“Mission Plan” Chapter 3 Introduction ISS and JEM SMILES Payload Field of View (FOV) Altitude Scanning of the Antenna Global Coverage Interference with FOV Antenna Response Pattern ISS Orbit and Attitude Variations Tangent Height Calibration Spectral Regions and Sensitivity Observation Frequency Bands Frequency Down-conversion Acousto-optic Spectrometer Sensitivity Brightness Temperature Calibration Conclusion Feb. 21, 2001, Kyoto JEM-SMILES

Introduction ISS and JEM SMILES Feb. 21, 2001, Kyoto JEM-SMILES

Japanese Experiment Module: “KIBO” SMILES Feb. 21, 2001, Kyoto JEM-SMILES

Instruments SMILES: Superconducting Submillimeter-wave Limb-emission Sounder View in the Cryostat Feb. 21, 2001, Kyoto JEM-SMILES

Signal Flow Feb. 21, 2001, Kyoto JEM-SMILES

Receiver Sensitivity: SIS vs SBD SBD mixer receiver SIS mixer receiver hf/k: Quantum Limit Superconductive SIS mixer receivers have some 20 times higher sensitivity than conventional Schottky-diode mixer receivers for frequencies less than 700 GHz. Feb. 21, 2001, Kyoto JEM-SMILES

Inside the SIS Mixer Mount Developed by NASDA in-house activity. 640 GHz SIS Mixer Inside the SIS Mixer Mount Developed by NASDA in-house activity. 0.4 mm Nb/AlOx/Nb Mixer Device Fabricated at NAOJ, Nobeyama Feb. 21, 2001, Kyoto JEM-SMILES

Cryostat Radiation Shield: MLI (40 layers) Signal Input Window: IR Filters (‘Zitex’) Support for 100 K Stage: S2-GFRP Straps (12 pieces) Support for 20 K Stage: GFRP Pipes (4 pieces) Support for 4 K Stage: CFRP Pipes (4 pieces) Feb. 21, 2001, Kyoto JEM-SMILES

4 K Mechanical Cooler Cooling to 100 K & 20 K: Cooling Capacity: 20 mW @ 4.5 K 200 mW @ 20 K 1000 mW @ 100 K Power Consumption: 300 W @ 120 VDC Mass: Cooler 40 kg Cryostat 26 kg Electronics 24 kg Total 90 kg Cooling to 100 K & 20 K: Two-stage Stirling Cooler Cooling to 4.5 K: Joule-Thomson Cooler Feb. 21, 2001, Kyoto JEM-SMILES

Mechanical Components of Coolers Cold-head and Compressor for Two-stage Stirling Cooler Two Compressors for Joule-Thomson Cooler Feb. 21, 2001, Kyoto JEM-SMILES

Sub-mm Receiver Subsystem To Antenna Ambient Temperature Optics AOPT Cryostat To Cold-Sky Terminator AAMP Single Sideband Filter CREC Sub-mm LO Source He Compressor (JT) He Compressor (ST) Feb. 21, 2001, Kyoto JEM-SMILES

Acousto-Optical Spectrometer Bandwidth: 1200 MHz x 2 units IF: 1.55 - 2.75 GHz / unit Focal Plane: 1728-ch. CCD array x 2 units Frequency Resolution: 1.8 MHz (FWHM) Channel Separation: 0.8 MHz / ch. AD Conversion: 12-bit, 2-CCD readouts in 4.9 msec Adder Output: 16 bits x 1728 ch. x 2 units in 500 msec AOS (Astrium & OPM) Feb. 21, 2001, Kyoto JEM-SMILES

Field of View (FOV) Altitude Scanning of the Antenna Global Coverage Interference with FOV Antenna Response Pattern ISS Orbit and Attitude Variations Tangent Height Calibration Feb. 21, 2001, Kyoto JEM-SMILES

Atmosphere Scanning A single spectral profile is acquired in every 0.5 sec, in which the antenna moves 0.056 deg in six angular steps. Feb. 21, 2001, Kyoto JEM-SMILES

Antenna Response Pattern Effective Pattern: Integrated over AZ angles Averaged for six consecutive EL points involved in a unit data Feb. 21, 2001, Kyoto JEM-SMILES

Height Resolution (Antenna) Angular Width (or Interval) [deg] Linear Width (or Interval) at Tangent Point Heights: 10 – 60 km [km] ISS: 350 km ISS: 400 km ISS: 460 km HPBW 0.096 3.82 – 3.24 4.08 – 3.51 4.41 – 3.82 Sampling Interval 0.05625 2.25 – 1.92 2.42 – 2.10 2.60 – 2.26 A refraction effect is included, which is significant for TPH < 20 km. Feb. 21, 2001, Kyoto JEM-SMILES

Global Coverage Trajectory for 24 Hours The Arctic Region Covered Latitudes: 68N – 35S (ISS Yaw: +15 deg) 65N – 38S (ISS Yaw: 0 deg) 61N – 42S (ISS Yaw: -15 deg) Horizontal Sampling Interval: about 360 km in orbital direction Feb. 21, 2001, Kyoto JEM-SMILES

Direction of Line-of-sight Feb. 21, 2001, Kyoto JEM-SMILES

FOV Interference Blue: with Main Beam by Solar Paddle Orange: with CST by SUN Red: with Main Beam by SUN FOV Interference Feb. 21, 2001, Kyoto JEM-SMILES

ISS Orbit Feb. 21, 2001, Kyoto JEM-SMILES

ISS Attitude Feb. 21, 2001, Kyoto JEM-SMILES

How to Determine Tangent Point Height HCS: Heliocentric Coordinate System GCS: Geocentric Coordinate System Feb. 21, 2001, Kyoto JEM-SMILES

Errors in Tangent Point Height (1-s level) Causes of Errors Bias [km] Random [km] Errors in Attitude: Sub-mm beam offset errors 5.02 - Mechanical driving errors 0.27 Thermal bending errors 0.12 Mechanical alignment errors STT measurement errors 0.06 Time synchronization errors 0.50 0.18 Errors in Altitude: ISS positional errors 0.30 0.10 Overall Error with the beam offset 5.07 0.34 Overall Error w/o the beam offset 0.76 Feb. 21, 2001, Kyoto JEM-SMILES

Spectral Regions and Sensitivity Observation Frequency Bands Frequency Down-conversion Acousto-optic Spectrometer Sensitivity Brightness Temperature Calibration Feb. 21, 2001, Kyoto JEM-SMILES

Expected Spectra: Band-A Limb Scanning A Feb. 21, 2001, Kyoto JEM-SMILES

Expected Spectra: Band-B Feb. 21, 2001, Kyoto JEM-SMILES

Expected Spectra: Band-C Limb Scanning C Feb. 21, 2001, Kyoto JEM-SMILES

Frequency Down-conversion Feb. 21, 2001, Kyoto JEM-SMILES

Single Sideband Filter Feb. 21, 2001, Kyoto JEM-SMILES

Effect of Image Band (1) Feb. 21, 2001, Kyoto JEM-SMILES

Effect of Image Band (2) Feb. 21, 2001, Kyoto JEM-SMILES

AOS: Differential Non-linearity Feb. 21, 2001, Kyoto JEM-SMILES

Standing Waves Feb. 21, 2001, Kyoto JEM-SMILES

Expected Sensitivity Feb. 21, 2001, Kyoto JEM-SMILES

Sensitivity and Accuracy Causes Sensitivity Accuracy of Absolute Brightness Excess Brightness Radiometric Noise Gain Variation Gain Non-linearity Standing Waves DNL* in AOS Knowledge Errors** * Differential non-linearity of the A/D converter. ** Concerning antenna characteristics and temperature measurement errors. Feb. 21, 2001, Kyoto JEM-SMILES

Accuracy of Absolute Brightness Temp. Feb. 21, 2001, Kyoto JEM-SMILES

Conclusions (1) Feb. 21, 2001, Kyoto JEM-SMILES

Conclusions (2) Feb. 21, 2001, Kyoto JEM-SMILES

Conclusions (3) Feb. 21, 2001, Kyoto JEM-SMILES