1. The Status of Dual-Frequency Multi-Constellation SBAS Trial by Japan
IS-GNSS 2017
Hong Kong, China
Dec , 2017
The Status of Dual-Frequency
Multi-Constellation SBAS Trial by Japan
Takeyasu Sakai
Electronic Navigation Research Institute
National Institute of Maritime, Port and Aviation Technology, Japan

2. Introduction SBAS: Satellite-Based Augmentation System
IS-GNSS in Hong Kong, Dec. 2017
Introduction
SBAS: Satellite-Based Augmentation System
International standard augmentation system primarily for aviation.
International standard by ICAO (International Civil Aviation Organization).
Transmits Augmentation information from the SBAS satellite.
Augments GPS in terms of accuracy and integrity.
Current standard: Single-frequency SBAS on L1.
US WAAS, Japanese MSAS, European EGNOS, Indian GAGAN.
Japan has been operating its own SBAS called MSAS since 2007.
MSAS: MTSAT-based Augmentation System.
Horizontal navigation service within Japanese airspace.
DFMC SBAS: The Second Generation SBAS
Dual-Frequency Multi-Constellation SBAS using L5 frequency.
Standardization activities ongoing by the ICAO.
ENRI is now conducting DFMC SBAS Experiment.
The First DFMC SBAS experiment with live L5 signal from the space.

3. SBAS Architecture Monitors consistency of GNSS signals on the ground.
IS-GNSS in Hong Kong, Dec. 2017
SBAS Architecture
SBAS Satellite
GNSS
Satellites
Ground Monitor Network
Users
Uplink
Station
GNSS Signals
SBAS Signal
Monitors consistency of GNSS signals on the ground.
Transmits differential correction and integrity information via SBAS satellite.

4. MSAS Program MSAS: SBAS Program by Japan MSAS GEO Satellites
IS-GNSS in Hong Kong, Dec. 2017
MSAS Program
MSAS: SBAS Program by Japan
JCAB (Japan Civil Aviation Bureau) decided the development of its own SBAS in 1993.
The system named MSAS, or MTSAT Satellite-based Augmentation System, was originally planned to be operational in 2000.
Launch of the MTSAT-1 was unfortunately failed in 1999.
MSAS GEO Satellites
MTSAT (Multi-functional Transport Satellite): Aviation and weather missions.
MTSAT works for AMSS and SBAS services for aviation.
MTSAT-1R and MTSAT-2 were launched in 2005 and 2006, respectively.
Beginning of Operation
Broadcast test signal since summer Certification activities for 2 years.
Finally, MSAS began its operation in September 27, 2007.
Available for Enroute to NPA (non precision approach) flight modes.

5. MTSAT Coverage (Fukuoka FIR) Decommissioned in 2015 MTSAT-1R @140E
IS-GNSS in Hong Kong, Dec. 2017
MTSAT Coverage
(Fukuoka FIR)
Decommissioned
in 2015
MTSAT-2 @145E
FIR: Flight Information Region

6. Current Configuration
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Current Configuration
Ranging Signals
GPS Satellites
Ground
Network
Naha GMS
Fukuoka GMS
Tokyo
GMS
Sapporo
Hitachi-Ota MCS
(and GMS)
Kobe MCS
Users
MTSAT-2
Augmentation Signals
6 GMS
in Japan
PRN137
PRN129
MSAS Monitor Stations
1 GEO, 2 MCS (Master Control Station) and 4 GMS (Ground Monitor Station);
MCS also has GMS function; MSAS has 6 domestic monitor stations.
MTSAT-2 is broadcasting 2 signals from 2 MCS (PRN129 and PRN137).

7. Performance GPS only GPS only MSAS PRN129 MSAS PRN137
IS-GNSS in Hong Kong, Dec. 2017
Performance
GPS only
GPS only
Horizontal
0.722m RMS
Horizontal
0.717m RMS
MSAS PRN129
MSAS PRN137
GEONET (Takayama) 16/8/8-12 (5 days)
PRN129 and PRN137 Broadcast Signal

8. Continuous Operation Current status: Replacement in 2020:
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Continuous Operation
Current status:
MTSAT-1R decommissioned in MTSAT-2 will be in 2020.
2 MRS sites decommissioned in 2015.
The ground facilities need to be upgraded: It is difficult to maintain 20-year old equipment.
Replacement in 2020:
MSAS continues operation with 1 GEO and 6 GMS until 2020.
In 2020, MSAS will continue operation with a GEO of the QZSS.
QZSS (Quasi-Zenith Satellite System): Japanese regional satellite navigation system with IGSO and GEO satellites.
The L1Sb signal of QZS-3 (GEO) will be used for MSAS service.
MCS equipment will also be fully replaced at the same time.
7 GMS will be added: Totally 13 GMS domestic.
Performance will be similar with the current MSAS: Horizontal only.

9. MSAS Evolution Plan Replacement in 2020: MSAS V2
IS-GNSS in Hong Kong, Dec. 2017
MSAS Evolution Plan
Replacement in 2020: MSAS V2
MSAS continues operation with 1 GEO and 6 GMS until 2020.
In 2020, MSAS will continue operation with a GEO of the QZSS.
QZSS (Quasi-Zenith Satellite System): Japanese regional satellite navigation system with IGSO and GEO satellites.
The L1Sb signal of QZS-3 (GEO) will be used for MSAS service.
7 GMS will be added: Totally 13 GMS domestic.
Supporting vertical guidance: MSAS V3
Vertical guidance: LPV and LPV-200 operation.
Will be supported in accordance with introduction of the 2nd GEO in 2023.
Dual-Frequency operation: MSAS V4
Eliminates ionospheric effects dramatically.
Robust vertical guidance (LPV and LPV-200) in the whole coverage area.
QZSS GEO will have L5 SBAS signal for dual-frequency operation.

10. MSAS Evolution Plan L5 SBAS trial since 2017.
IS-GNSS in Hong Kong, Dec. 2017
MSAS Evolution Plan
L5 SBAS trial since 2017.
Replacement to the new QZSS-based system in 2020.
LPV/LPV-200 upgrade in 2023 and L5 SBAS implementation after that.

11. DFMC SBAS DFMC (Dual-Frequency Multi-Constellation) SBAS
IS-GNSS in Hong Kong, Dec. 2017
DFMC SBAS
DFMC (Dual-Frequency Multi-Constellation) SBAS
The second generation SBAS following L1 SBAS.
Using L5 SBAS signal instead L1.
Eliminates ionospheric effects thanks to dual-frequency operation.
Vertical guidance service everywhere in the coverage.
Standardization activities ongoing by the ICAO.
ENRI is now conducting DFMC SBAS Experiment
The First L5 SBAS experiment with real L5 signal from the space.
Using QZSS L5S signal transmitted from GEO (QZS-3) and IGSO (QZS-2/4).
Prototype DFMC SBAS for the experiment has been developed.
GPS/GLONASS/Galileo-capable dual-frequency SBAS.
Compliant with the draft standards of DFMC SBAS being discussed at ICAO.
Began the experiment on 23 Aug. via L5S signal of QZS-2 IGSO.
Expects transmission from QZS-3 GEO by end of this year.
Contributes to standardization activities by the ICAO.

12. (Hitachi-Ota, Ibaraki)
IS-GNSS in Hong Kong, Dec. 2017
Configuration
QZSS
#2, #3, and #4
GLONASS
GPS
Galileo
GEO (QZS-3) +
IGSO (QZS-2/4)
Ranging Signal
L5S Signal
L5S Signal
Uplink
BeiDou
Measured
OBS
L5 SBAS
Message
GEONET
ENRI L5 SBAS
Prototype
QZSS C&C
GSI
(Shinjuku, Tokyo)
ENRI, MPAT
(Chofu, Tokyo)
QZSS MCS
(Hitachi-Ota, Ibaraki)
Supports DFMC
Provides observation in real time
Operates in real time
Dual-Frequency
Supports GPS, GLONASS, and Galileo
Uplink L5 SBAS message stream for transmission

13. Prototype DFMC SBAS 13 Monitor Stations
IS-GNSS in Hong Kong, Dec. 2017
Prototype DFMC SBAS
13 Monitor Stations
Dual Frequency
DFMC L5 SBAS
Location:
GEONET
(Wakayama)
Period:
2016/12/15 (24H)
SBAS corrections improve position accuracy in both modes of GPS and GPS+GLONASS.
SBAS messages are generated by the prototype DFMC SBAS developed by ENRI in accordance with the draft DFMC L5 SBAS standards.

14. Prototype DFMC SBAS Horizontal Accuracy Vertical Accuracy
IS-GNSS in Hong Kong, Dec. 2017
Prototype DFMC SBAS
w/o augmentation
w/ augmentation
Horizontal Accuracy
Vertical Accuracy
Evaluated long-term performance using archive data at GEONET Wakayama.
Confirmed stable performance for a year; Horizontal ~0.5m and Vertical ~1m.

15. Clock/Orbit Correction
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Real Time Experiment
Output Message Stream
Clock/Orbit Correction
Position Solution
Satellites in Sky
Monitored
Satellites
5 GPS
No GLONASS
7 Galileo
2 QZSS
Galileo SV-8

16. Conclusion SBAS: International Standard Augmentation System
IS-GNSS in Hong Kong, Dec. 2017
Conclusion
SBAS: International Standard Augmentation System
Augments GNSS in terms of accuracy and integrity.
Available: US WAAS, Japanese MSAS, European EGNOS, Indian GAGAN.
Japan has been operating its own SBAS called MSAS since 2007.
The standardization of DFMC SBAS is ongoing by the ICAO.
DFMC SBAS Experiment Using QZSS L5S Augmentation Signal
The First L5 SBAS experiment with real L5 signal from the space.
ENRI has developed the prototype SBAS for experiments.
GPS/GLONASS/Galileo-capable dual-frequency SBAS.
Compliant with the draft standards of DFMC SBAS being discussed.
The experiment has been conducted since 23 August, 2017.
Contact for more information:
Dr. Takeyasu Sakai
Electronic Navigation Research Institute
National Institute of Maritime, Port and Aviation Technology, Japan