Current status of Quasi-Zenith Satellite System Japan Aerospace Exploration Agency QZSS Project Team 1
Quasi-Zenith Satellite System The QZSS is a regional space-based PNT (Positioning, Navigation and Timing) system covers East Asia and Oceania region and transmits six civil PNT signals; L1C/A, L1C on 1575.42 MHz, L2C on 1227.60 MHz and L5 on 1176.45 MHz L1-SAIF on 1575.42 MHz LEX on 1278.75MHz can provide seamless PNT services by combining usage with GPS. Increasing coverage and availability of PNT services even in downtown and mountainous areas. can enhance GPS performance by transmitting error correction and integrity information. can accelerate Modernization of GPS in Asia Oceania region. can be a suitable platform for Multi-GNSS augmentation. First satellite will be launched in 2010. The 2nd and 3rd satellite will be approved after assessment of the technical demonstration result. 2
Quasi-Zenith Satellite System Three satellites are in elliptical and inclined GSO in different orbital planes to pass over the same ground track. a=42,164km e=0.06-0.09 i=39-47deg Ω= 120deg apart 3
Latitude (deg) 30 Quasi-Zenith Satellite System 90 60 30 QZSS coverage and Visibility in Asia & Oceania 10 20 20 30 40 50 30 60 Minimum Elevation Angle and Ground Track 50 60 70 40 20 30 20 10 10 0 60 50 40-30 50 50 60 10-60 10 20 30 40 20 10-90 0 30 60 90 120 150 180 210 240 270 300 330 360 Longitude (deg) Ground Track of a QZSS Satellite At least one QZSS satellite can be observed more than specified elevation angle any time. For instance, users in orange colored area can receive at least one QZSS satellite with 70 degrees or more. 4
Quasi-Zenith Satellite System Coverage Average visible satellite number for QZSS (3 SV constellation) Southeast Asia can observe 3 QZSS satellites almost of time. 0 1 2 3 Most East Asia and Oceania countries can observe more than 2 QZSS satellites every time 5
Planned Signals L1-C/A L1C L2C L5 Frequency 1575.42MHz 1227.6MHz 1176.45MHz Notes Complete compatibility and interoperability with existing and future modernized GPS signals Differential Correction data, Integrity flag, Ionospheric correction Almanac & Health for other GNSS SVs L1-SAIF * 1575.42MHz Compatibility with GPS-SBAS LEX 1278.75MHz Experimental Signal with higher data rate message (2Kbps) Compatibility & interoperability with Galileo E6 signal * L1-SAIF: L1-Submeter-class Augmentation with Integrity Function 6
Development Status - Space Segment - - MICHIBIKI- Mass Power Design Life Approx. 1,800kg (dry) (NAV Payload:Approx. 320kg) Approx. 5.3 kw (EOL) (NAV Payload: Approx. 1.9kW) 10 years Radiation Cooled TWT TWSTFT Antenna C-band TTC Antenna Laser Reflector L1-SAIF Antenna L-band Helical Array Antenna Satellite Configuration on Orbit 7
Development Status - Space Segment - Proto-flight Tests are on going IPT(20/8/2009-3/9/2009) Initial Alignment Test (5/9/2009-10/9/2009) Preparation for TVT TVT (1/10/2009-30/10/2009) Electrical Performance Test (21/11/2009-22/11/2009) Alignment Test after TVT (23/11/2009-25/11/2009) Sine Vibration Test (7/12/2009-6/1/2010) 8
Summary QZSS is a regional space-based PNT system covers East Asia and Oceania region and transmits six civil PNT signals. Proto-Flight tests of QZS-1 are being conducted. First satellite (QZS-1; MICHIBIKI) will be launched in 2010. 9
Current status of SPAC Application Development Satellite Positioning Research and Application Center General Manager Yasushi SAKURAI 10
Political Back Ground of the QZSS Private Sector Organization for promoting utilization Supporting Companies Collaboration Academic World Coordination Participation & Support SPAC Collaboration Japan Business Federation Government Collaborative Research Policy Recommendation Satellite Positioning Research and Application Center Participation Research Contract R&D Organizations Participation Coordination as private sector Global GNSS Collaboration Research Contract GNSS/GIS Industries & Organizations Satellite Positioning Research and Application Center (SPAC) was established in 5 February 2007 approved by the Ministers associated with QZSS research and development (MEXT, MIC, METI and MLIT) to promote navigation satellite technology application and consequential geo-spatial information utilization (http://www.eiseisokui.or.jp/en/) - 11-11
Application of QZSS Augmentation Service QZSS GPS Galileo GLONASS Upload Augmentation Data Acquisition Support Data Correction Data Integrity Data Navigation Signal and Message + Signal Master Control Station Augmentation Data L1-SAIF Signal (250bps) LEX Signal (2000bps) High Speed Rail Augmentation Data Japanese Geodetic Generation Datum Global Monitoring Station Survey Low Speed Machines(Construction, etc) 2cm LEX Signal 20cm Cars Accuracy L1-SAIF Signal Mobile/Personal Navigation 1m 12
L1-SAIF Application Demonstration Plans (1) Safety Protection of Children and Elderly Persons by Watching Positions (2) Natural Disaster Detection and Action Support (3) Service Innovation 13
LEX Application Demonstration Plan (1) Mobile Positioning System for Nationwide Base Map 3 3 3 2 4 14
LEX Application Demonstration Plan(Cont.) (2) Precision Agriculture based on it Automatic Driving 15
Summary SPAC has been investigating application of regional spacebased PNT system, focusing high precision L1-SAIF and LEX with industrial partners. Both L1-SAIF and LEX systems and terminals are now under development. Application demonstration is planned to be started from the beginning of the next year. 16