準天頂衛星システム（構想から7機体制の実現、11機体制に向けて）
JAXA 小暮 聡
2023年9月12日：QBIC第28回社会実装推進(拡大)ＷＧ

2023/09/11
13th Anniversary
for the 1st
Michibiki satellitelaunch◼ みちびき初号機～実用システム整備（過去）◼ 7機体制へ（現在）◼ 11機体制へ（未来）みちびき以前（～early 2000s）⚫ 準天頂軌道⚫
⚫

静止軌道の混雑緩和、中高緯度地帯での高仰角サービス
NICT 田中氏、木村氏（平成25年度宇宙開発利用大賞受賞）⚫ 地域衛星測位システム構想⚫
⚫

NASDA：河野氏ら
JRANSA：NEC、伊藤忠高橋氏ら⚫ 移動体衛星通信システム構想
⚫
⚫

三菱電機
日立製作所

2002年6月
準天頂衛星システム開発利用推進協議会設置
官民連携プロジェクト

2002年11月
新衛星ビジネス株式会社設立

みちびき以前（～early 2000s）⚫

民間事業化断念
⚫
⚫

⚫

2006年

新衛星ビジネス（株）→（財）衛星測位利用推進センター（SPAC）
国による実証衛星打ち上げに政策による後押し⚫
⚫
⚫

地理空間情報活用推進基本法施行々基本計画
宇宙基本計画 2009年6月

2007年8月29日
2008年4月

みちびき初号機⚫

省庁連携プロジェクト⚫

⚫

文科省（JAXA）、総務省（NICT）、国土交通省（国土地理院、ENRI、国総研）、経産省（AIST）、SPAC

2010年9月11日打上げ、2011年6月22日
アラートフラグ解除
Route

GPS alone
GPS+MICHIBIKI⚫

GPS補完実証、利用実証⚫

実証実験終了後、内閣府移管
2017年2月28日⚫

2022年3月25日運用終了(C)2011ZENRIN(Z05E-008)

実用システム（～2-4号機）⚫
⚫

PFI事業（～2032年まで）
システム構築⚫ 2013年度より地上システム整備⚫ 2017年6月1日 2号機打ち上げ⚫ 2017年8月19日 3号機打ち上げ⚫ 2017年10月10日 4号機打ち上げ⚫ 2021年10月26日 初号機後継機⚫

2018年11月1日サービスイン⚫ GPS補完⚫ GNSS補強 （CLAS、SLAS）⚫ メッセージング（安否、災危通報）

みちびき7機体制拡張⚫ 2023年度～24年度 5号機から7号機を順次打上げ、7機体制を構築⚫ 地域衛星測位システム⚫
⚫

日本近傍において常時4機以上の準天頂衛星信号受信
日本独自の衛星測位（持続測位）⚫ サービス拡張⚫
⚫
⚫

災危通報サービス＋L/Jアラート＋海外向けEWSS
MADOCA-PPP
信号認証（QZNMA）

7 Satellites Constellation of QZSS•

3 additional satellites will be on Inclined Geosynchronous Orbit, Geostationary orbit at 90.5 EastLongitude, and Quasi Geostationary Orbit on 175 West Longitude.

•

7 SVs QZSS can provide independent PNT capability for more resilient applications

QZS-5
QZS-1R
QZS-5

QZS-1R
North pole
QZS-6(GEO)

QZS-3
QZS-3(GEO)

QZS-2

QZS-6
QZS-7(QGEO)

QZS-7

QZS-2

QZS-4

QZS-4

South pole

Satellite orbit

Satellite
NumberOrbital
Position

Inclined
GeosynchronousOrbit（4 satellites)

QZS-1R
QZS-2
QZS-4
QZS-5

148 deg E
139 deg E
139 deg E
139 deg E

Geostationary Orbit（2 satellites）

QZS-3
QZS-6

127 deg E
90.5 deg E

Quasi
Geostationary Orbit（1 satellite）

QZS-7

175 deg W

7-QZSS Ground Track

4 IGSO + 2 GEO +1 QGEO constellation will be completed around 2024
9

7 Satellites Constellation of QZSS
◼ Additional services start around 2024


PNT service◼ Users obtain PVT solution with using ranging signals provided by 7 SV constellations.
◼ Target accuracy is 1-meter horizontal error (95 percentile).
◼

Navigation Message Authentication(NMA) will be added to LNAV, CNAV, CNAV2
messages.

 MADOCA-PPP service◼ Covering major part of eastern hemisphere and providing PPP error corrections on L6signal.
 Early/Emergency Warning Service (EWS)◼ Four out of seven SVs will transmit 122 bits common EWS message on L1S signal.

Common EWS message is being finalized under collaboration with EC, Cabinet office, andISRO. It will be published after approval at ICG-17 meeting.
◼ Additional bits on QZSS EWS can be available for regional unique information sharing.
◼

10

Practical PPP correction service in Asia Pacific region•

Test live signal of MADOCA-PPP is now available for Asia-Pacific region.

•Operational service will start no later than 2024.

•For reduction of initial convergence period in PPP, QZSS will provide the ionospheric correction data forsome areas from 2024 as an experiment for future practical operation.
Ionospheric correction
data will be provided via
L6D signal on QZS 5-7.

Error corrections for PPP
will be provided via L6E
signal on QZS 1-7.

SV orbit error
Clock error

Code /phase Bias
Ionospheric delay
Tropospheric delay

QZS#1-4
L6D:
CLAS

QZS#1-7
L6E:
PPP corr.

✔
✔
✔
✔
✔

✔
✔
✔

QZS#5-7
L6D:
Fast-PPP Ex✔

Fast PPP convergence time can be achieved withQZSS wide area ionospheric correction.

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QZSS EWSS for Asia Pacific region◼ Ground control segment upgrade is on-going, real-time operation will be realized in 2024-2025.
JFY

2018

Current operation201920202021◼
①2023

20242025～

DCR operation (Metrological warning delivery)*Nov. 1stService start

Upgrade plan
Message for Asia Pacificcountries

2022

Manufacturing, Test
①Trial by Manual preparation★
★
★
Trial by EU Trial Trial
at AU at PH by AU★

★

MGA RPD Challenge★

②Trial by semi manualoperation(ftp connection)③Real timeoperation(VPN connection)

Step by step approach to practical operation
Trial by Manual preparation
Message is received by e-mail and prepared by manual.

②

Trial by semi manual operation
Message is received by ftp and prepared by system. The message will bebroadcasted within 2mins(e.g.).

③

Real time operation
Message is received by VPN and prepared by system. The message will bebroadcasted real-timely.

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QZSS EWSS Demonstrations◼ To promote utilizing QZSS, CAO conducts QZSS EWS Demonstration in the Asia-pacific region.
◼ The first demonstration campaign will be conducted in 2022-2023 and the second one will be held in2023-2024.
➢ 1st Demo Campaign: Prototype system evaluation from alert generation to alert notification via QZSS
➢ 2nd Demo Campaign: Realistic demo considering actual local operation protocol with local first responders.

◼ Those demonstration campaigns will be conducted by NTT DATA which is contracted by CAO.

➢➢

Field Survey has successfully completed in Thailand and Fiji, the demonstration implementation,schedule, and scenario generally were agreed.
In conjunction with MGA 13th Annual conference in Chiang Mai, demo was conducted with local
stakeholders, Sony, GISTDA, CMU with using dust sensors, LPWA communications(ELTRES),and QZSS EWS.
Baan Pa Tueng Ngam Village, Thailand

Candidate site for demonstration in Fiji

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QZSS QZNMA Service▌QZSS navigation message authentication (QZNMA) service will be lunched in 2024. Navigation messages
in the following signals are authenticated with using ECDSA (P-256).
➢ QZSS signals (L1C/A, L1C, L5) are protected by self-authentication➢ GNSS signal (GPS: L1C/A, L1C, L5, Galileo:E1b, E5a) are protected by cross-authentication (L6E)
GNSS Satellites(GPS, Galileo)
All QZS SatellitesQZSSNavigation
Message

User
Users＋

DigitalSignature

Navigation
MessagevsDigital
Signature

MasterGroundStationGroundcontrolstation
Public Key+Authentication System

Drafted Interface specification of QZNMA (IS-QZSS-SAS) has been published in Jan. 2023
https://qzss.go.jp/technical/download/ps-is-qzss.html

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11機体制へ• 宇宙基本計画改定2023年6月

Future evolution of QZSS architecture◼ Constellation expansion beyond 7 satellites
 Several options were investigated. Following 11 satellites constellation is an example.

⚫ Improving✓ Positioning Accuracy✓ System Reliability (redundancy)

GSO and QGSO satellites in 7 satellites constellation
IGSO satellites in 7 satellites constellation

Additional 4SVs (IGSO)
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