Latest QZSS status
February 14, 2024
Satoshi Kogure
Executive Advisor for Space Policy Committee, Cabinet Office, Government of JapanQZSS Overview -Current Services◼ Functional Capabilities:
 GPS Complementary (Ranging signals)
 GNSS Augmentation (Error corrections) Messaging Service (Disaster relief, management)◼ Coverage: Asia and Pacific region
 Augmentation service covers only Japan◼

Experimental service provides error corrections in Asia Pacific region

4050
60
QZSS-1

10QZSS-2
QZSS-4
QZSS-3(127E)

One or more QZSS SVs over 10 degrees elevation angle2QZSS Overview -SystemQZS-1R
QZS-1◼ Constellation:

QZS-2, 4

 1 GEO Satellite, 127E
 3 QZO Satellite (IGSO)◼ Ground System
 2 Master Control Stations

QZS-3Equator◼ Hitachi-Ota and Kobe

 7 Satellite TTC Stations◼ Located south-western islands

QZSS Control Center, Hitachi-Ohta, Over 30 Monitor Stations

around the world3

QZSS Development Plan
• Development of 3 additional satellites are on-going.
• The launches for them are scheduled for JFY2024 to 2025 on the formal plan.
JFY2017

2018

2019

1st MichibikiIn-Operation

2020

2021

2022

2023

2024

20252026～

Launch 1stMichibiki
replacement
satellite

Launch No.2,3,4

QZSS
4-Sat.
Constellation Official Service Launch

QZSS Service
SBAS Service

November 1, 2018

QZSS Feasibility Study
7-Sat.
Constellation

QZSS Service

Development of No.5,6,7

Today

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7 Satellites Constellation of QZSS
◼ Additional services start around 2024-2025
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 L6 signal.

 Early/Emergency Warning Satellite Service (EWSS)◼ Four out of seven SVs will transmit 122 bits common EWS message on L1S signal.

Common EWS message is developed under collaboration with EC, Cabinet office, and ISRO
under ICG framework and CAMF(Common Alert Message Format) has been published sinceJanuary 2024 by EC.
◼ Additional bits on QZSS EWS can be available for regional unique information sharing.
◼

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

QZS#1-5
L6D:
CLAS

QZS#1-7
L6E:
PPP corr.

◼ Fast PPP with ionospheric correction
Ionospheric correction data will be providedvia L6D signal on QZS 6-7, with using
regional/nation CORS observation data.

QZS#6 and #7
L6D:
Fast-PPP Ex

SV orbit error
Clock error

Code /phase Bias
Ionospheric delay
Tropospheric delay

Fast PPP coverage will be depending on thepartnership of regional/nation CORS operators.

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Practical PPP correction service in Asia Pacific region◼ PS-QZSS 003 was published on Mar. 17, 2022
Adding MADOCA-PPP service to the existing services◼ Defines augmented constellations and signals
 QZSS, GPS, Galileo and Glonass◼ Service area At least one QZS is visible more than 10 degrees elevation angle
 Error corrections for more than 20 satellites over 10 degrees elevation angle are available in the service area.

◼ Minimum performance level Positioning Accuracy▪ Horizontal: 30cm (95%)▪ Vertical:50cm (95%)
 Convergence time▪ 1800 sec▪ 600 sec (target value for initial convergence time withionospheric correction)± 60 latitude and 70E to 200E longitude

https://qzss.go.jp/en/technical/ps-is-qzss/ps-is-qzss.html
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Practical PPP correction service in Asia Pacific region◼

IS-QZSS-MDC 002 was published in November, 2023
 Defining L6E channel properties and data format
 RF specifications are same as CLAS(L6D)◼ Same receiver H/W can be available for tracking and decoding MADOCA-PPP error corrections

 Data format is changed from the existing experimental signal on L6E and Compact-SSR format, same asCLAS, is adopted.
◼ Updated error corrections will be provided from the beginning of October 2022.

 The definition and data format for wide area ionospheric corrections has been added.
◼

Test evaluation result, Service Performance Report MADOCA-PPP, was also posted QZSS web site.

[Evaluation Period]: Dec. 1 to Dec. 31,[Evaluation Period]: Dec. 1 to Dec. 31, 2022 Source; M. Kishimoto, “Latest Status of QZSS”, ION GNSS+ 2023

https://qzss.go.jp/en/technical/ps-is-qzss/ps-is-qzss.html

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Overview of QZSS EWSS
◼ “Satellite Report for Disaster and Crisis Management” service (DCReport) is being provided

with using L1S signal.
 Same RF property as L1 SBAS, 1575.42MHz, BPSK(1), 500sps(250bps)
 1 of 4 slots (every 4seconds) sharing with SLAS service (2 of 4 slots in 4 seconds)
 MT43 is defined the information issued by Japan Meteorological Agency such as theearthquake, typhoon, tsunami, volcanic eruption and so on, in IS-QZSS-DCR-010.
 MT44 will be extended for EWS.
Common EWS message with 122 bits and additional 78 bits
◼ Common EWS includes disaster type, target area, and alert, guidance information.
◼ Target area for an alert msg. is defined by ellipse and its radius is adjustable.
◼ MT44 interface for oversea users is under development.
◼

PAB: Preamble
MT: Message type
Rc: Report Classification
Oc: Organization CodeVn: Version Number
Rsv: Reserved
CRC: Cyclic Redundancy Check

DIRECTION OF DATA FLOW FROM SATELLITE; MOST SIGHIFICANT BIT (MSB) TRANSMITTED FIRST

250 BITS – 1 SECOND
1915 18 24

PAB MT Rc Oc
6386BITS BITS BITS BITSDATA FIELD 191 BITS

215 221

DCR(MT43)

Vn Rsv
66BITS BITS

EWS message(MT44): 122 bits

Additional 78 bits

227
CRC
24BITS

Report category ：1 Maximum priority, 2 Priority, 3 Regular, 7 Training/Test
Message type : 43, 44(DC report), 47～50 (SLAS), etc.

9QZSS EWSS for Asia Pacific region◼ Ground control segment upgrade is on-going, official operation will start from JFY2025.
JFY

2018

Current operation201920202021

◼
①2024

2025～

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

★

★

★

MGA RPD Challenge②Trial by semi manualoperation(ftp connection)③Officialoperation(ftp connection)

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

②2023

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

Upgrade plan
Message for Asia Pacificcountries

2022

①

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

③Official operation
After modifications extracted through the above Trial operation, official operation
will start form JFY 2025. (with ftp I/F and within 2 min alert broadcasting fromuser’s alert issue.

②,③10

QZSS QZNMA Service▌QZSS navigation message authentication (QZNMA) service will be lunched in 2024. Navigation messages inthe 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)▌The Interface Specification (IS-QZSS-SAS-001)(draft-002) is now available on our website.
▌Test Transmission started from the end of July 2023.
GNSS Satellites(GPS, Galileo)
All QZS Satellites
QZSS
Navigation
Message

Users
User＋Digital
Signature

Navigation
MessagevsDigital
Signature

Groundcontrolstation
Master Ground
StationPublic Key+Authentication System11QZSS Constellation Expansion Plan◼ Three Advantage of11SV constellation
1.

2.
3.

Higher and morestable accuracyMore resilient androbust system
Wider service
coverage● QZO satellite: ■ GEO satellite

14th MGA conference, K. Mikami “QZSS Michibiki Overviews for East Asia and Japan”

12Asia-Oceania Collaborations with QZSS
Vietnam for MADOCA-PPP
Signed the LoI with VNSC to conduct demonstrationof MADOCA-PPP.

Bangladesh for EWSS
Planning for seminars and promotions with local disasterprevention organization (MDMR, etc) in JFY2023

Nepal for EWSS
Planning for seminars and promotions with localorganizations (MOHA, etc) in JFY2023

Thailand for EWSS/MADOCA-PPP
EWSS) Performed demonstration with GISTDA
for forest fires in JFY2022. Planning second
demonstration in March 2024. MADOCA-PPP) Under
evaluating positioning performance with GISTDA.

Philippines for EWSS/MADOCA-PPP
EWSS) Planning for seminars and promotions with local
disaster prevention organization (OCD) in JFY2023
MADOCA-PPP) Signed the LoI with NAMRIA to conduct
demonstration of MADOCA-PPP.

Indonesia for EWSS/MADOCA
EWSS) Planning for seminars and promotions
with local disaster prevention organization(BNPB, University of Indonesia ) in JFY2023
MADOCA-PPP) Signed the LoI with BIG and BRIN toconduct demonstration and seminars of MADOCA-PPP.

Fiji for EWSS
Performed demonstration with NDMO toevacuate residents and tourists fromTsunami in JFY2022.
Planning second demonstration in JFY2023.

Cambodia for EWSS
Planning for seminars and promotions with localorganization (NCMD) in JFY2023

Malaysia for EWSS
Performed of seminars and promotions with local
disaster prevention organization (NADMA, etc) in August,2023

Australia for EWSS
Performed demonstration with GA
for forest fires in JFY2022. Planningsecond demonstration by mainly
university in JFY2023.

14th MGA conference, K. Mikami “QZSS Michibiki Overviews for East Asia and Japan”

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QZSS Applications
Autonomous driving
QZSS compatible
antenna(Built in shark fin)

Buoy for real-time ocean tide monitoring
QZSS compatible
antenna(Built in shark fin)

QZSS
Cloud ServerAI（© Nissan Motor Co., Ltd.)（©Honda R&D Co., Ltd.）

Wearable terminals
display the distanceto the greenDrones

mobile / satellitecommunications
Buoy

GNSS Receiver and Chipset

display the EWS
message

Agricultural Drone

CORE Corp.
Cohac∞Ten+(for CLAS,MADOCA)
150*210*55mm

Septentrio
Mosaic-CLAS
31*31*4mm

Logistics drone

Bizstation Corp.
RWS.DC(for CLAS,MADOCA)
50*51.5*13.1mm

Magellan Systems Japan
MJ-3021-GM4-QZS-EVK(for CLAS,MADOCA)
130*90*42 mm

u-bloxZED-F9P + NEO-D9C(for CLAS)

Magellan Systems Japan
Digital ASIC**(for CLAS,MADOCA)
Less than 30*40 mm* Additional android software for MADOCA-PPP** to be available in the end of March 2023

14QZSS Applications for Smart Cities◼ Planning and early construction phase Enough infrastructure has not established the area
 MADOCA-PPP support effective drone survey, construction machine control andetc.…
◼ Autonomous Mobility, Logistics
 GNSS is most important key technology for precise positioning and timing, QZSS canprovide error corrections for autonomous mobility and logistics.
 QZNMA can provide secure position and timing against emerging spoofing threats.
◼ Precise Time Synchronization
 Sub nano-second time synchronization for finance applications, traffic control systemand so on.
 Using phased array antenna tracking a QZSS satellite can strengthen anti-jammingcapability.
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Summary• QZSS is Japanese regional navigation satellite system to improve not only GNSS availability butalso accuracy and reliability– 4 satellite constellation: Three IGSO and one GEO satellites• Future expansion to 7 satellite constellation– Three additional satellites will be launched in JFY2024 to JFY2025. QZSS will provide independent PNT capability
for more reliable applications.

• 11 SV constellations will realize more stable, robust performance and wider service coverage.
• New services– QZNMA will provide message authentication capability to users, applying ECDSA (P-256).
– MADOCA-PPP will become operational service no later than 2024 and also EWSS covering Asia Pacific region.

• Commercial devices and applications– Emerging new applications such as autonomous driving, drone operation with some commercial devices.
– According to applications for the smart cities, QZMNA and time sync are most likely expected to strengthen
resilience.

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Thank you for your attention!
For more information, please visit our web site
https://qzss.go.jp/en/

Question?

kogure.satoshi@jaxa.jp

Acknowledgement:
QZSS strategic office, CAO, provided slides for this presentation. Many thanks to their contributions and supports.
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