Introduction of QZSSUN GNSS Training Programme
January 12, 2022
Satoshi Kogure
Space Technology Directorate I, JAXAContents
QZSS Overview

1.
••

•

Future Expansion to 7SV constellation

2.
•

3.

SystemServices and Performances
Program schedule

Service expansion into Asia Pacific region

Summary1

1.QZSS Overview -System◼ Constellation:

QZS-1

QZS-2, 4

 1 GEO Satellite, 127E
 3 QZO Satellite (IGSO)◼ Ground System

QZS-3

Equator 2 Master ControlStations◼ Hitachi-Ota and Kobe

 7 Satellite TTC Stations

QZSS Control Center, Hitachi-Ohta,◼ Located south-westernislands Over 30 Monitor Stations

around the world2

1.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

405060QZSS-1

10

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

One or more QZSS SVs over 10 degrees elevation angle

3

1. QZSS Overview -Current Services▌Current Performance (PNT service SIS User Range Accuracy)[ Evaluation Period ]2020/08/31～ 2021/09/01[ Evaluation Results ]Specification: Less than 2.6 m (95%)
AverageBest dayWorst day

QZS-1

0.55 m

0.41 m

1.94 mQZS-2

0.75 m0.43 m1.15 mQZS-3

0.64 m

0.46 m1.20 m

QZS-4

0.83 m0.56 m1.45 m

Improvement of the ranging accuracy ofQZS-1 to 4 is now on going.
41. QZSS Overview -Current ServicesQZSS Augmentation Service

Augment 13 satellites (GPS L1C / A,QZS L1C / A) to utilize 13 monitor
station.

Utilize real-time Continuously Operating
Reference System (CORS) data.

VerticalNarrow

1.0m

2.0m

Wide

2.0m

3.0m

95%%

Horizontal

Accuracy

Accuracy95

Disaster reports could broadcast at 4second intervals using SLAS slots.

Augmentation

CLAS : cm augmentation

Augmentation

SLAS : sub m segmentation |SBAS＠
LPV200 GEO with

Ionosphere and troposphere correction
information is provided in 13 block units.

Horizontal

VerticalFixed

6cm

12cm

Mobile

12cm

24cm

SBAS
receiver
LNAVRNPAPCH
MDH≧250ft

LPV 200
Like as ILS CAT-Ⅰ
DH＝200～250ft

https://qzss.go.jp/info/archive/h
onda_210517.html

Level.3＠Honda Legend

GPSSBAS

LNAV/VNAV
GPS＋Baro
ALTDH≧250ft

LPLike as
LOC/TDME
MDH≧250ft

https://qzss.go.jp/info/archive/lbj_210510.html

Level.2＠Nissan Ariya

5

1. QZSS Overview -Current ServicesCLAS Enhancement
Centi-meter Level Augmentation Service (CLAS) has
been broadcasting the signal compliant with IS-QZSSL6-003 (*1) using the L6D signal of the all the QuasiZenith Satellites (QZS-1, 2, 3, and 4), which increases
the number of augmented satellites to a maximum of17 for more stable positioning accuracy since Nov 30,2020.

the number of augmented satellites(Oct 6, 2020 during trial operation)
the number ofvisible satellites(average)

All epochs

16.4

the number of augmentedsatellites(average)
Conventional
formatNew format

9.8

16.0

Assumed condition for Urban Area
FixFloat
Independent positioning
Number of satellites visible(Elevation Mask: 40[deg])

Positioning Accuracy
in the Conventional format

Positioning Accuracy
in the New format

Positioning Error
N-S [m]Positioning Error
E-W [m]Positioning Error
Vertical [m]Number of satellites
available forpositioning [unit]
HDOP・Horizontal (95%) : 40.6 [cm]・Horizontal (95%) : 6.1[cm]・Vertical (95%): 128.3 [cm]・Vertical (95%): 22.1[cm]・FIX rate: 98.2 [%]・FIX rate: 99.4[%]*1) https://qzss.go.jp/en/technical/ps-is-qzss/ps-is-qzss.html

6

1. QZSS Overview -Current ServicesMessaging Services outline
Satellite Report for Disaster and Crisis Management (DC Report)
QZSS

Disaster Info. provided by JMA suchas Tsunami, Volcanic eruption,
weather warning and so on.

⚫ Using margin of L1S signal⚫ Domestic service, only generated
JMA is available currently.
Using one of four slots of L1S:1575.42MHz,
once a four seconds, 250 bits short code cantransmit disaster management info withapplicable location
DC Report available Handset(GNSS Rx, Car Navigation device)

Disaster Info.

Japan
MeteorologicalAgency (JMA)

Ground Control
Segment

Rx can select the Info which shown the devices
depending on their location

7

QZSS Development Plan
• Development of 3 additional satellites have been started from 2019.
• QZSS will start 7 satellite constellation service around 2023
JFY201720182019

2020

2021

2022

2023

2024

2025～Launch 1st Michibiki
replacement satellite

1st Michibiki
In-Operation
Launch No.2,3,4

QZSS
4-Sat.
Constellation Official Service Launch

QZSS Service
SBAS Service

November 1, 2018

QZSS
7-Sat.
Constellation

Feasibility Study

Development of No.5,6,7

Today

QZSS Service8

Latest Launch© Mitsubishi Electric Corp.

© Mitsubishi Heavy Industry• QZS-1R was successfully launched on 26th of October 2021
– By H-IIA launch vehicle #44, from Tanegashima Space Center– Replacing the first Michibiki satellite, QZS-1– QSS, system operator, is tuning their POD S/W to start providing
operational service performance.
92. Future Expansion to 7SV constellation•3 additional satellites will be on Inclined Geosynchronous Orbit,
Geostationary orbit on 90.5 East Longitude, 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(GEO)
QZS-3

QZS-6

QZS-7
QZS-2
QZS-2

QZS-4

QZS-4

7-QZSS Ground Track

QZS-7(QGEO)South pole

Satellite orbit

SatelliteNumberOrbital
Position

Inclined
GeosynchronousOrbit（4 satellites)

QZS-1RQZS-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

4 IGSO + 2 GEO +1 QGEO
constellation will be completed
around 2023

10

2. Future Expansion to 7SV constellation▌Visibility at Tokyo11

2. Future Expansion to 7SV constellation■ Visibility at other Asian cities
Sky plot at Bangkok

Sky plot at Jakarta

103060 7070 degree

Sky plot at Singapore
64 degree1030
60 7074 degree122. Future Expansion to 7SV constellation
Practical PPP correction service in Asia Pacific region•Experimental augmentation 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, QZS will provide the ionosphericcorrection data for some areas from 2024 as an experiment for future practical operation.

Ionospheric correction data will beprovided via L6D signal on QZS 5-7.

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

QZS#1-4
L6D:
CLAS

QZS#1-7
L6E:
PPP corr.

✔
✔
✔

Ionospheric delay✔
✔
✔
✔

Tropospheric delay✔

SV orbit error
Clock error
Code /pahse Bias

QZS#5-7
L6D:
Fast-PPP Ex✔

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

13

2. Future Expansion to 7SV constellation
Early Warning Service (EWS)• QZSS L1S signal is sharing 250 bps data stream with SLAS and Disaster andCrisis Report service.
• DCR service is currently providing weather information generated by JMA forJapanese domestic users.
• Common EWS format is being investigated in collaboration with EC and India.
• QZSS ground segment will be upgraded to support EWS in 2024-2025.
SignalService Name

Center freq.

Modulation

Bit Rate

L1S

Sub-meter Level Augmentation Service(SLAS)

1575.42MHz

BPSK

250bpsDC Report ServiceRoad Map for QZSS EWS expansion into Asia Pacific region
JFY

2018

Current operation
Upgraded plan
EWS expansion intoAsia Pacific region

2019

2020

2021

2022

2023

2024

2025～

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

Manufacturing, Test
①Trial by Manual preparation★
★
Trial by EU ★
Trial★
in AU Trial in AU Trial
in PH
in Thailand②Trial by semi manualoperation(ftp connection)③Real timeoperation(VPN connection)

14

2. Future Expansion to 7SV constellation
Early Warning Service (EWS)• QZSS L1S signal is sharing 250 bps data stream with SLAS and Disaster andChallenges
be solved in advance of practical operation;
Crisis Reportto
service.
• Due
DCRto
serviceis currently
providingweather
information throughgeneratedby JMAfornarrow
bandwidthof satellitetransmission
QZSS
L1S,Japanese domestic users.
effective
way to share it among stakeholders in the region, some• Common EWS format is being investigated in collaboration with EC and India.
prioritization scheme will be required.
• QZSS ground segment will be upgraded to support EWS in 2024-2025.
SignalService NameCenter freq.

Modulation

Bit Rate

L1S

Sub-meter Level Augmentation Service(SLAS)

1575.42MHz

BPSK

250bpsDC Report Service

Road Map for QZSS EWS expansion into Asia Pacific region
JFY2018

Current operation
Upgraded plan
EWS expansion intoAsia Pacific region

20192020

20212022202320242025～

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

Manufacturing, Test
①Trial by Manual preparation★
★
Trial by EU ★
Trial★
in AU Trial in AU Trialin PHin Thailand②Trial by semi manualoperation(ftp connection)③Real timeoperation(VPN connection)

15

IS-QZSS-PNT update• Update the interface specification for PNT– New PRN codes were assigned for QZS-5, 6, and 7.
– Change L1C/A to L1C/B after QZS-1R satellite.
• Due to the interference mitigation into GPS C/A, QZSS will transmit L1C/A or L1C/B signal within the agreed interference level.
• L1 C/B has BOC(1,1) wave form instead of BPSK(1) for L1 C/A, with same PRN
code family and data format, LNAV.

“IS-QZSS-PNT-004”
https://qzss.go.jp/en/technical/ps-is-qzss/ps-is-qzss.html

16

Available Receiver, chipset for QZSS use

MADOCA-PPPavailable

CLAS available

SLAS, EWS available

Most of smart phone can track QZSS

17

Available Receiver, chipset for QZSS use

MADOCA-PPPavailable

CLAS available

SLAS, EWS available

List of products that support the QZSS is shown;https://qzss.go.jp/en/usage/products/list.html
Most of smart phone can track QZSS18

Summary• QZSS is Japanese regional navigation satellite system to improve
not only GNSS availability but also accuracy and reliability– 4 satellite constellation: Three IGSO and one GEO satellites• Cabinet Office has been providing PNT, augmentation andmessaging services with good performances since Nov. 1, 2018.
– The service performance has satisfied with the specifications.
– CLAS performance is enhanced with increasing augmented satellite number.

• Future expansion to 7 satellite constellation– Started procurement process for additional 3 satellites around 2023
• An IGSO, a GSO and a QGSO satellite will be added to the existing constellation– MADOCA-PPP will become operational service no later than 2024 and also
EWS

• Latest launch, for QZS-1R, on Oct. 26, 2021, wascompleted successfully.
19Thank you for your attention!
For more information, please visit our web site
https://qzss.go.jp/en/Question? 📨 kogure.satoshi@jaxa.jp
20

2. QZSS 7SV Constellation Design▌Visibility at Nagarkot, Nepal21

2. QZSS 7SV Constellation Design▌Visibility in Nagarkot, Nepal

QZS-3 Elevation 34 deg
QZS-6 Elevation 57 deg

22