The Status of Dual-Frequency Multi-Constellation SBAS Trial by Japan IS-GNSS 2017 Hong Kong, China Dec. 10-13, 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

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.

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.

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 2005. Certification activities for 2 years. Finally, MSAS began its operation in September 27, 2007. Available for Enroute to NPA (non precision approach) flight modes.

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-1R @140E MTSAT-2 @145E FIR: Flight Information Region

Current Configuration IS-GNSS in Hong Kong, Dec. 2017 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).

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 940058 (Takayama) 16/8/8-12 (5 days) PRN129 and PRN137 Broadcast Signal

Continuous Operation Current status: Replacement in 2020: IS-GNSS in Hong Kong, Dec. 2017 Continuous Operation Current status: MTSAT-1R decommissioned in 2015. 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.

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.

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.

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.

(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

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 950369 (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.

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 950369 Wakayama. Confirmed stable performance for a year; Horizontal ~0.5m and Vertical ~1m.

Clock/Orbit Correction IS-GNSS in Hong Kong, Dec. 2017 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

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 <sakai@mpat.go.jp> Electronic Navigation Research Institute National Institute of Maritime, Port and Aviation Technology, Japan