National Institute of Information and Communications Technology Overview of the Small Optical TrAnsponder (SOTA) Project Space Communications Laboratory Wireless Networks Research Center National Institute of Information and Communications Technology (NICT) National Institute of Information and Communications Technology Satellite mass v.s Data rate of Satellites ever launched 1.0E+12 TerraSAR-X WorldView1 1.0E+09 EROS-B Formosat2 GeoEye-1 Orbview3Kompsat2 ALOS Orbview4 JERS1 EOS-PM1 Ikonos2 Radarsat1 QuickBird2 TopSat ERSEnvisat1 Lewis Landsat ADEOS Spot RazakSat-1 UK-DMC2 MOS 1B MOS 1A Terra IRS-1A,1B,1C UK-DMC1 EROS-A AS1000 AlSat Orbview2 TRMM satellites [bps] 1.0E+06 EarlyBird Micro satellitesMicroLabSat Cute-1.7 PRISM Data rateData for Earth observation TOMS-EP Cute-I 1.0E+03 1 10 100 1000 10000 Satellite mass [kg] 2 National Institute of Information and Communications Technology Laser-Communication Infrastructure for Micro-Satellites Short-term space verification High-end communications by micro satellites by mid/small satellites (2~3 years) (5~ years) 1.0E+12 Mid/small satellites Quasi-real-time Gbps data transmission TerraSAR-X via site diversity WorldView1 1.0E+09 EROS-B Formosat2 GeoEye-1 Orbview3Kompsat2 ALOS Orbview4 JERS1 EOS-PM1 New area covered Ikonos2 Radarsat1 Offline QuickBird2 TopSat ~100Mbps ERSEnvisat1 by SOCRATES/SOTA Lewis Landsat ADEOS Spot transmission RazakSat-1 UK-DMC2 MOS 1B MOS 1A Terra IRS-1A,1B,1C only Optical UK-DMC1 EROS-A AS1000 AlSat Orbview2 TRMM satellites [bps] 1.0E+06 ~Mbps EarlyBird Micro satellitesMicroLabSat Cute-1.7 RF PRISM Data rateData for Earth observation ~kbps TOMS-EP Cute-I 1.0E+03 1 10 100 1000 10000 Satellite mass [kg] 3 National Institute of Information and Communications Technology Research Activities on Space Laser Communications in NICT 1995 2000 2005 2010 2015 2020 ETS-VI (KIKU6) ETS-IX 1994-1995 2021 GEO-GND OICETS (KIRARI) 2005-2009 http://www.jaxa.jp/projects/sat/ets6/index_j.html SOCRATES 2014-2016 RISESAT GEO-GND with Tohoku Univ. LEO-GND 2017? http://www.jaxa.jp/projects/sat/oicets/index_j.html LEO-GND LEO-GND GEO-LEO 4 National Institute of Information and Communications Technology Overview of SOTA SOTA: Small Optical TrAnsponder Data rate : 1 〜 10 Mbps Wavelength : Tx 0.8 / 0.98 / 1.55 µm Rx 1.064 µm Beam pointing : Az - El mount + Fine-pointing mirror SOCRATES衛星に 組み込まれたMassSOTA : 6.2 kg (including optical and control part) One of the smallest optical-communication terminals for spacecraft equipment 5 National Institute of Information and Communications Technology Development of SOTA Project started PDR CDR Launch End of operation 2010 2011 2012 2013 2014 2015 2016 2017 Checkout Experiments Coarse sensor SOTA QKD lasers Fine sensor Workshop Receiver Transmitting Laser BBM model PFM model Mass: 5.3 kg, Power: 22.8 W Mass: 6.2 kg, Power: 39.5 W Size: W149xD188xH160 Size: W65xD114xH138 6 National Institute of Information and Communications Technology Major Specifications of SOTA 5.9 kg (incl. both the optical Mass part & electric part) Sleep Stand- Tx2,3, Power Tx1 mode by 4 consumption 1.7W 2.0W 15.7W 12.6W Az: >±50deg, Gimbal range SOTA-OPT El: -22deg~+78deg Link range Less than1000 km Tx1: 976 nm Tx2 and Tx3 : 0.8 μm Wavelength Tx4 : 1549 nm Rx: 1064 nm, Acquisition/Tracking: 1064 nm Data Rate 1Mbps / 10Mbps (selectable) Photograph and Layout of SOTA-PFM optics (Proto Flight Model) 7 National Institute of Information and Communications Technology Small Satellite “SOCRATES” Satellite bus developed by AES SOTA Solar Paddle © AES Size W496 x D495 x H485 mm Mass : 48kg Attitude control : 3-axis stabilization 8 National Institute of Information and Communications Technology Optical Ground Station in Koganei (1-m Diameter) Koganei - 1-m diameter reflective telescope - Improved tracking ability for LEO satellites - Focus availability: 5 ports (Cassegrain, Nasmyth, Coude…) Major specification Mount Altazimuth Focus Classical Cassegrain Diameter f1000 mm D/f F12 Tracking accuracy LEOs < 10 arcsec Stars < 0.4 arcsec (EL > 30 deg.) Stars < 1 arcsec (EL=15~30 deg.) Angle coverage Azimuth ±270 deg. Elevation 15~88 deg. Total mass 7.5 t Tube mass 1.3 t Nasmyth payload mass 1 t (max) 9 National Institute of Information and Communications Technology Launch 24th of May, 2014 Piggyback satellite of the ALOS-2 “DAICHI-2” Advanced Land Observing Satellite http://h2a.mhi.co.jp/mission/results/index.html Orbit : Sun-synchronous sub-recurrent orbit Altitude : 628km 10 National Institute of Information and Communications Technology - Configuration of SOTA Experiment - Ground system 3) Beacon laser Small satellite system Small Optical Optical ground 4) Tx laser Direct Small TrAnsponder Comm. station (OGS) camera (NICT Koganei) (SOTA) Data & control Image data signals & control 2) Commands Small satellite bus 6) Telemetry 1) Parameters TT&C TT&C station 5) Telemetry data *TT&C: Tracking, Telemetry and Control 11 National Institute of Information and Communications Technology Schedule of Conducted Experiments Date Event May 24, 2014 SOCRATES Launch ~ July Check out of the satellite ~ Oct. Check out of the OGS and the SOTA Nov. ~ Experiments for the NICT May, 2015 ~ Start of international experiment campaign Resumption of international experiment Spring, 2016 ~ campaign 12 National Institute of Information and Communications Technology Statistics of Total 184 Passes Satellite Trouble Both 2 passes Uplink – Downlink Established 47 passes 26% Bad Weather Forecast No Go 67 passes 38 % Go 62 % 21% Only Uplink Established 21 passes Failed (due to Satellite) Failed (due to OGS) 17 passes 30 passes 13 National Institute of Information and Communications Technology Success Criteria No. Experiment items Contents Status Minimum success Start-up check of M1 Demonstration of COTS parts Done equipment Confirmation of optical M2 Demonstration of COTS parts Done sensors etc. Success Confirmation of orbit, bus attitude control and mounted S1 Tracking test Done equipment Acquisition of the received signal, data acquisition at Propagation data S2 different wavelengths (Uplink: 1064nm / Downlink: Done acquisition TX1, TX4) S3 BER measurement Downlink: TX1, TX4 Done Full success Data transmission Confirmation of data transmission functions ( Data: F1 Done experiment CAM / PRBS / Sample image ) ( Downlink: TX1, TX4) F2 Error correcting code LDGM and RS codes Done Extra success Polarization Weak coherent pulses are measured by single photon E1 Done measurement counting detectors (SPCMs). Experiment with other international optical ground E2 International experiment Done stations (OGSs) except for Koganei OGS. 14 National Institute of Information and Communications Technology Site-Diversity Technology Weather-monitoring stations Whole-sky monitor camera Optical communication satellite Cloud Laser beam OGS control center OGS http://sstg.nict.go.jp 15 National Institute of Information and Communications Technology Optical Ground Stations Network Koganei 1m Koganei 1.5m Okinawa 1m Kashima 1m 16 National Institute of Information and Communications Technology Overview of In-orbit Experimental Results with SOTA • Overview of the SOTA project • NICT’s New OGS • In-orbit performance of SOTA • Atmospheric-turbulence analysis • BER measurement • Data-transmission experiment • Error-correcting code experiment • QKD-related experiments • LEO-satellite optical observation with NICT portable telescope • Optical detection for SOTA downlink experiment using SSPD • International joint-experiment campaign 17 National Institute of Information and Communications Technology Summary (1) Space-to-ground laser-communication experiments with the SOTA terminal have been successfully conducted. (2) Almost all of the success criteria from minimum- to extra-success have been done, including international experiments. (3) World first lasercomm technology for a 50-kg- class micro-satellite was verified with several international partners globally, which has opened the door to a variety of applications to be exploited soon with the rise of mega-constellations. 18 .