t. sakai, s. fukushima, and k. ito electronic navigation research institute, japan t. sakai, s....

T. Sakai, S. Fukushima, and K. ItoElectronic Navigation Research Institute, Japan

T. Sakai, S. Fukushima, and K. ItoElectronic Navigation Research Institute, Japan

Recent Development ofQZSS L1-SAIF Master Station

Recent Development ofQZSS L1-SAIF Master Station

ION ITM 2010ION ITM 2010San Diego, CASan Diego, CA

Jan. 25-27, 2010Jan. 25-27, 2010

ION ITM 25-27 Jan. 2010 - ENRIION ITM 25-27 Jan. 2010 - ENRI

SSLIDELIDE 22IntroductionIntroduction

• QZSS (Quasi-Zenith Satellite System) programQZSS (Quasi-Zenith Satellite System) program::– Regional navigation service broadcast from high-elevation angle by three satelliRegional navigation service broadcast from high-elevation angle by three satelli

tes on the inclined geosynchronous (quasi-zenith) orbit;tes on the inclined geosynchronous (quasi-zenith) orbit;

– Currently working for launch of the first satellite in 2010 Summer season;Currently working for launch of the first satellite in 2010 Summer season;

– Broadcast GPS-compatible supplemental signals on three frequencies and two Broadcast GPS-compatible supplemental signals on three frequencies and two augmentation signals, L1-SAIF and LEX.augmentation signals, L1-SAIF and LEX.

• L1-SAIF L1-SAIF (Submeter-class Augmentation with Integrity Function) signal offers(Submeter-class Augmentation with Integrity Function) signal offers::– Sub-meter accuracy wide-area differential correction service;Sub-meter accuracy wide-area differential correction service;

– Integrity function for safety of mobile users; andIntegrity function for safety of mobile users; and

– Ranging function for position availability; all on L1 single frequency.Ranging function for position availability; all on L1 single frequency.

• ENRI has been developing L1-SAIF signal and facilityENRI has been developing L1-SAIF signal and facility::– Signal design: GPS/SBAS-compatible on L1;Signal design: GPS/SBAS-compatible on L1;

– Implemented L1-SAIF Master Station (L1SMS) which generates augmentation Implemented L1-SAIF Master Station (L1SMS) which generates augmentation message stream in realtime and transmits it to QZSS MCS.message stream in realtime and transmits it to QZSS MCS.


SSLIDELIDE 33

Part 1Part 1

Overview of QZSS ProgramOverview of QZSS Program


SSLIDELIDE 44QZSS ConceptQZSS Concept

QZSQZSGPS/GEOGPS/GEO

• Signal from high elevation angleSignal from high elevation angle

• Applicable to navigation services for Applicable to navigation services for mountain area and urban canyonmountain area and urban canyon

• Footprint of QZS orbitFootprint of QZS orbit• Centered 137ECentered 137E• Eccentricity 0.1, Inclination 45degEccentricity 0.1, Inclination 45deg


SSLIDELIDE 55QZSS ProgramQZSS Program

• QZSS (Quasi-Zenith Satellite System) programQZSS (Quasi-Zenith Satellite System) program::– Japan has been developing QZSS since FY 2003;Japan has been developing QZSS since FY 2003;

– Regional navigation service broadcast from high-elevation angle by three satelliteRegional navigation service broadcast from high-elevation angle by three satellites on the inclined geosynchronous (quasi-zenith) orbit;s on the inclined geosynchronous (quasi-zenith) orbit;

– Broadcast GPS-compatible supplemental signals on three frequencies (L1 C/A, LBroadcast GPS-compatible supplemental signals on three frequencies (L1 C/A, L1C, L2C, and L5) and two augmentation signals, L1-SAIF and LEX.1C, L2C, and L5) and two augmentation signals, L1-SAIF and LEX.

• Participating institutesParticipating institutes::– JAXA (JAXA (Japan Aerospace Exploration AgencyJapan Aerospace Exploration Agency):): Development and operation of the spac Development and operation of the spac

e segment and Master Control Station;e segment and Master Control Station;– NICT (NICT (National Institute of Information and Communication TechnologyNational Institute of Information and Communication Technology):): Frequency stan Frequency stan

dard and time keeping system including Uplink Station;dard and time keeping system including Uplink Station;– AIST (AIST (National Institute of Advanced Industrial Science and TechnologyNational Institute of Advanced Industrial Science and Technology):): Time synch-ron Time synch-ron

ization between space and ground;ization between space and ground;– GSI (GSI (Geographical Survey InstituteGeographical Survey Institute):): Survey-grade carrier-based positioning service; Survey-grade carrier-based positioning service;– ENRI (ENRI (Electronic Navigation Research InstituteElectronic Navigation Research Institute):): Navigation-grade WADGPS service b Navigation-grade WADGPS service b

roadcast by L1-SAIF signal.roadcast by L1-SAIF signal.


SSLIDELIDE 66Overall ArchitectureOverall Architecture

Function distributed in each institute

Timing management by NICT, WADGPS service by ENRI, etc.

SLR SiteSLR SiteMonitor Monitor StationStation NW NW

GPS Satellites

TT&C / NAV Msg TT&C / NAV Msg Uplink StationUplink Station

GEONETGEONET(GSI)(GSI)

Time Mgmt Time Mgmt StationStation

TWSTFT: Two Way Satellite Time and Frequency TransferTWSTFT: Two Way Satellite Time and Frequency Transfer

QZS SatelliteQZS Satellite

User ReceiverUser Receiver

SatelliteLaser Ranging

Navigation SignalsL1: 1575.42 MHzL2: 1227.60 MHzL5: 1176.45 MHzLEX: 1278.75 MHz

TT&C / NAV Message Uplink

TWSTFTUp: 4.43453GHz

Down: 12.30669GHz

(Courtesy: JAXA QZSS PT)(Courtesy: JAXA QZSS PT)

Master Control Master Control Station (MCS)Station (MCS)


SSLIDELIDE 77Space Segment: QZS-1Space Segment: QZS-1

L-band Helical Array Antenna

L1-SAIF Antenna

Laser Reflector

C-band TTC Antenna

Radiation Cooled TWTTWSTFT Antenna

25.3m

MassApprox. 1,800kg (dry) (NAV Payload： Approx. 320kg)

PowerApprox. 5.3 kW (EOL) (NAV Payload: Approx. 1.9kW)

Design Life 10 years


SSLIDELIDE 88

• Supplemental signalsSupplemental signals::– GPS-compatible L1C/A, L2C, L5, and L1C signals working with GPS; For GPS-compatible L1C/A, L2C, L5, and L1C signals working with GPS; For

improving availability of navigation;improving availability of navigation;– With minimum modifications from GPS signal specifications;With minimum modifications from GPS signal specifications;– Coordination with GPS Wing on broadcasting L1C signal;Coordination with GPS Wing on broadcasting L1C signal;– JAXA is responsible for all supplemental signals.JAXA is responsible for all supplemental signals.

• Augmentation signalsAugmentation signals::– Augmentation to GPS; Possibly plus Galileo;Augmentation to GPS; Possibly plus Galileo;– L1-SAIF: Compatible with SBAS; reasonable performance for mobile users;L1-SAIF: Compatible with SBAS; reasonable performance for mobile users;– LEX: For carrier-based experimental purposes; member organizations may LEX: For carrier-based experimental purposes; member organizations may

use as 2kbps experimental data channel;use as 2kbps experimental data channel;– ENRI is working for L1-SAIF while JAXA is developing LEX.ENRI is working for L1-SAIF while JAXA is developing LEX.

• Interface Specification: IS-QZSSInterface Specification: IS-QZSS::– Specifies RF signal interface between QZS satellite and user receiver;Specifies RF signal interface between QZS satellite and user receiver;– First issue: Jan. 2007; Maintained by JAXA.First issue: Jan. 2007; Maintained by JAXA.

QZSS SignalsQZSS Signals


SSLIDELIDE 99QZSS Frequency PlanQZSS Frequency Plan

SignalSignal ChannelChannel FrequencyFrequency BandwidthBandwidth Min. Rx PowerMin. Rx Power

QZS-L1CQZS-L1CL1CDL1CD

1575.42 MHz1575.42 MHz

24 MHz24 MHz ––163.0 dBW163.0 dBW

L1CPL1CP 24 MHz24 MHz – – 158.25 dBW158.25 dBW

QZS-L1-C/AQZS-L1-C/A 24 MHz24 MHz – – 158.5 dBW158.5 dBW

QZS-L1-SAIFQZS-L1-SAIF 24 MHz24 MHz – – 161.0 dBW161.0 dBW

QZS-L2CQZS-L2C 1227.6 MHz1227.6 MHz 24 MHz24 MHz – – 160.0 dBW160.0 dBW

QZS-L5QZS-L5L5IL5I

1176.45 MHz1176.45 MHz25 MHz25 MHz – – 157.9 dBW157.9 dBW

L5QL5Q 25 MHz25 MHz – – 157.9 dBW157.9 dBW

QZS-LEXQZS-LEX 1278.75 MHz1278.75 MHz 42 MHz42 MHz – – 155.7 dBW155.7 dBW

Find detail in IS-QZSS document.Find detail in IS-QZSS document.


SSLIDELIDE 1010

Part 2Part 2

L1-SAIF Signal DesignL1-SAIF Signal Design


SSLIDELIDE 1111

• QZSS will broadcast wide-area augmentation signalQZSS will broadcast wide-area augmentation signal::– Called L1-SAIF (Submeter-class Augmentation with Integrity Function);Called L1-SAIF (Submeter-class Augmentation with Integrity Function);

– Developed by ENRI.Developed by ENRI.

• L1-SAIF signal offersL1-SAIF signal offers::– Wide-area differential correction service for improving position accuracy; TargeWide-area differential correction service for improving position accuracy; Targe

t accuracy: 1 meter for horizontal;t accuracy: 1 meter for horizontal;

– Integrity function for safety of mobile users; andIntegrity function for safety of mobile users; and

– Ranging function for position availability.Ranging function for position availability.

• Interoperable with GPS L1C/A and fully compatible with SBASInteroperable with GPS L1C/A and fully compatible with SBAS::– Broadcast on L1 freq. with RHCP; Common antenna and RF front-end;Broadcast on L1 freq. with RHCP; Common antenna and RF front-end;

– Modulated by BPSK with C/A code;Modulated by BPSK with C/A code;

– 250 bps data rate with 1/2 FEC; message structure is identical with SBAS;250 bps data rate with 1/2 FEC; message structure is identical with SBAS;

– Differences: Large Doppler and additional messages.Differences: Large Doppler and additional messages.

QZSS L1-SAIF SignalQZSS L1-SAIF Signal


SSLIDELIDE 1212WADGPS ConceptWADGPS Concept

Orbit CorrectionOrbit Correction

TroposphereTroposphere

IonosphereIonosphere

Ionospheric CorrectionIonospheric Correction

Tropospheric CorrectionTropospheric Correction

Clock CorrectionClock Correction• Same contribution to any user Same contribution to any user

location;location;• Not a function of location;Not a function of location;• Needs fast correction. Needs fast correction.

• Different contribution to different Different contribution to different user location;user location;

• Not a function of user location; but Not a function of user location; but a function of line-of-sight direction;a function of line-of-sight direction;

• Long-term correction.Long-term correction.

• Function of user location;Function of user location;• Up to 100 meters;Up to 100 meters;• Vertical structure may be Vertical structure may be

described as a thin shell.described as a thin shell.

• Function of user location, especially height of user;Function of user location, especially height of user;• Up to 20 meters;Up to 20 meters;• Can be corrected enough by a fixed model.Can be corrected enough by a fixed model.


SSLIDELIDE 1313SBAS/L1-SAIF Message StructureSBAS/L1-SAIF Message Structure

PreamblePreamble8 bits8 bits

Message TypeMessage Type6 bits6 bits

Data FieldData Field212 bits212 bits

CRC parityCRC parity24 bits24 bits

250 bits per second

MTMT

00

11

22～～ 55

66

77

99

1010

1212

1717

1818

ContentsContents

Test modeTest mode

PRN maskPRN mask

Fast correction & UDREFast correction & UDRE

UDREUDRE

Degradation factor for FCDegradation factor for FC

GEO ephemerisGEO ephemeris

Degradation parameterDegradation parameter

SBAS time informationSBAS time information

GEO almanacGEO almanac

IGP maskIGP mask

IntervalInterval[s][s]

66

120120

6060

66

120120

120120

120120

300300

300300

300300

2424

2525

2626

2727

2828

6363

FC & LTCFC & LTC

Long-term correctionLong-term correction

Ionospheric delay & GIVEIonospheric delay & GIVE

SBAS service messageSBAS service message

Clock-ephemeris covarianceClock-ephemeris covariance

Null messageNull message

66

120120

300300

300300

120120

——

MTMT ContentsContents IntervalInterval[s][s]

Transmitted FirstTransmitted First


SSLIDELIDE 1414SBAS/L1-SAIF Message (1)SBAS/L1-SAIF Message (1)

Message TypeMessage Type ContentsContents CompatibilityCompatibility StatusStatus

00 Test modeTest mode BothBoth FixedFixed

11 PRN maskPRN mask BothBoth FixedFixed

2 to 52 to 5 Fast correction & UDREFast correction & UDRE BothBoth FixedFixed

66 UDREUDRE BothBoth FixedFixed

77 Degradation factor for FCDegradation factor for FC BothBoth FixedFixed

1010 Degradation parameterDegradation parameter BothBoth FixedFixed

1818 IGP maskIGP mask BothBoth FixedFixed

2424 Mixed fast/long-term correctionMixed fast/long-term correction BothBoth FixedFixed

2525 Long-term correctionLong-term correction BothBoth FixedFixed

2626 Ionospheric delay & GIVEIonospheric delay & GIVE BothBoth FixedFixed

99 GEO ephemerisGEO ephemeris SBASSBAS FixedFixed

1717 GEO almanacGEO almanac SBASSBAS FixedFixed

1212 SBAS network timeSBAS network time SBASSBAS FixedFixed

88 ReservedReserved SBASSBAS FixedFixed


SSLIDELIDE 1515SBAS/L1-SAIF Message (2)SBAS/L1-SAIF Message (2)

Message TypeMessage Type ContentsContents CompatibilityCompatibility StatusStatus

2727 SBAS service messageSBAS service message SBASSBAS FixedFixed

29 to 5129 to 51 (Undefined)(Undefined) —— ——

2828 Clock-ephemeris covarianceClock-ephemeris covariance BothBoth FixedFixed

6262 ReservedReserved BothBoth FixedFixed

6363 Null messageNull message BothBoth FixedFixed

5252 TGP maskTGP mask L1-SAIFL1-SAIF TentativeTentative

5656 Intersignal biasesIntersignal biases L1-SAIFL1-SAIF TentativeTentative

5757 (Ephemeris-related parameter)(Ephemeris-related parameter) L1-SAIFL1-SAIF TBDTBD

5858 QZS ephemerisQZS ephemeris L1-SAIFL1-SAIF TentativeTentative

5959 (QZS almanac)(QZS almanac) L1-SAIFL1-SAIF TBDTBD

6060 (Regional information)(Regional information) L1-SAIFL1-SAIF TBDTBD

6161 ReservedReserved L1-SAIFL1-SAIF TentativeTentative

55３３ Tropospheric delayTropospheric delay L1-SAIFL1-SAIF TentativeTentative

54 to 5554 to 55 (Advanced Ionospheric delay)(Advanced Ionospheric delay) L1-SAIFL1-SAIF TBDTBD


SSLIDELIDE 1616GPS/L1-SAIF SimulatorGPS/L1-SAIF Simulator

• GPS/L1-SAIF SimulatorGPS/L1-SAIF Simulator::– Simulates GPS L1 C/A and QZSS L1-SAIF signals;Simulates GPS L1 C/A and QZSS L1-SAIF signals;

– Generates RF signals based on pre-defined GPS and QZSS constellation Generates RF signals based on pre-defined GPS and QZSS constellation scenario and signal specificationsscenario and signal specifications

of IS-GPS and IS-QZSS;of IS-GPS and IS-QZSS;

– Manufactured by Spirent, modifyingManufactured by Spirent, modifying

GPS/SBAS simulator GSS7700.GPS/SBAS simulator GSS7700.

• Special function for experimentSpecial function for experiment::– Added extra command to inputAdded extra command to input

L1-SAIF message from EthernetL1-SAIF message from Ethernet

port (TCP/IP);port (TCP/IP);

– L1-SAIF message is either inputL1-SAIF message is either input

by the command externally orby the command externally or

generated by the simulator internally.generated by the simulator internally.

GPS/L1-SAIFGPS/L1-SAIFSimulatorSimulator

GPS/L1-SAIFGPS/L1-SAIFReceiverReceiver


SSLIDELIDE 1717GPS/L1-SAIF ReceiverGPS/L1-SAIF Receiver

• Prototype GPS/L1-SAIF ReceiverPrototype GPS/L1-SAIF Receiver::– Receives GPS L1 C/A and QZSS L1-SAIF signals;Receives GPS L1 C/A and QZSS L1-SAIF signals;

– Decode and apply L1-SAIF message as defined by IS-QZSS;Decode and apply L1-SAIF message as defined by IS-QZSS;

– Manufactured by Furuno Electric.Manufactured by Furuno Electric.

• Special function for experimentSpecial function for experiment::– L1-SAIF message can be input fromL1-SAIF message can be input from

Ethernet port (TCP/IP)Ethernet port (TCP/IP) 　　 as well asas well as

L1-SAIF signal on RF;L1-SAIF signal on RF;

– Enable to process L1-SAIF and SBAS,Enable to process L1-SAIF and SBAS,

totally three, augmentation signalstotally three, augmentation signals

simultaneously;simultaneously;

– Portable equipage for experimentPortable equipage for experiment

at remote or on mobile.at remote or on mobile.



SSLIDELIDE 1818RF Compatibility TestRF Compatibility Test

• Ranging function: The receiver output the proper position solution with pseudorange of Ranging function: The receiver output the proper position solution with pseudorange of L1-SAIF signal generated by the simulator;L1-SAIF signal generated by the simulator;

• Decoding message: The receiver decoded L1-SAIF message which matched with the Decoding message: The receiver decoded L1-SAIF message which matched with the message input to the simulator via Ethernet port; The command needs to be given 2-smessage input to the simulator via Ethernet port; The command needs to be given 2-second before the applicable time of transmission;econd before the applicable time of transmission;

• Successfully completed in Feb. 2009.Successfully completed in Feb. 2009.

GPS/L1-SAIFGPS/L1-SAIFSimulatorSimulator


TCP/IPTCP/IP

RF CableRF Cable

SpirentSpirent Furuno ElectricFuruno Electric

FileFile

L1-SAIF MessageL1-SAIF Message

ScenarioScenario

Decoded MessageDecoded Message

CompareCompare

L1-SAIF SignalL1-SAIF Signal

ENRI (Chofu, Tokyo)ENRI (Chofu, Tokyo)


SSLIDELIDE 1919RF Compatibility TestRF Compatibility Test

Standalone GPSStandalone GPS L1-SAIF AugmentationL1-SAIF Augmentation

2008/9/10 00:05:00 to 06:00:00 (6 hours)2008/9/10 00:05:00 to 06:00:00 (6 hours)

OK!OK!


SSLIDELIDE 2020

Part 3Part 3

L1-SAIF Master Station (L1SMS)L1-SAIF Master Station (L1SMS)


SSLIDELIDE 2121

• L1-SAIF Master Station (L1SMS):L1-SAIF Master Station (L1SMS):– Generates L1-SAIF message stream in realtime and transmits it to QZSS MCS deGenerates L1-SAIF message stream in realtime and transmits it to QZSS MCS de

veloped by and installed at JAXA;veloped by and installed at JAXA;– Installed at ENRI, Tokyo; 90km from JAXA Tsukuba Space Center;Installed at ENRI, Tokyo; 90km from JAXA Tsukuba Space Center;– Subsystems: GEONET Server, Primary Receiver, Interface Processor, Message GSubsystems: GEONET Server, Primary Receiver, Interface Processor, Message G

enerator, Ionosphere Processor, Troposphere Processor, and Batch Processor.enerator, Ionosphere Processor, Troposphere Processor, and Batch Processor.

ENRI L1SMSENRI L1SMS

L1SMSL1SMSGEONETGEONET

QZSQZS

QZSS MCSQZSS MCS

GPSGPS

MeasuredMeasuredDataData

L1-SAIFL1-SAIFMessageMessage

GSIGSI ENRIENRI JAXAJAXA

L1-S

AIF S

ignal

L1-S

AIF S

ignalL1C/A, L2P

L1C/A, L2PL1

C/A, L

2P

L1C/A

, L2P K-band

K-bandClosedClosedLoopLoop


SSLIDELIDE 2222L1SMS Installed at ENRIL1SMS Installed at ENRI

StorageStorage

Router toRouter toGEONETGEONET

I/FI/F

UPSUPSUPSUPS

MessageMessageGeneratorGenerator

GEONETGEONETServerServer

StorageStorage

Ionosphere Ionosphere ProcessorProcessor

StorageStorage


SSLIDELIDE 2323Configuration of L1SMSConfiguration of L1SMS

GEONET ServerGEONET Server

Ionosphere ProcessorIonosphere ProcessorTroposphere ProcessorTroposphere Processor

Message GeneratorMessage Generator(L1SMG)(L1SMG)

GEONETGEONET

Batch ProcessorBatch Processor(IFB Estimation)(IFB Estimation)

L1SMS Batch SubsystemL1SMS Batch Subsystem

L1SMS Realtime SubsystemsL1SMS Realtime Subsystems

TCP/IPTCP/IP

MessageMessageOutputOutput

via TCP/IPvia TCP/IP

ObservationObservationFile (RINEX)File (RINEX)

via FTPvia FTP

IFBIFBEstimatesEstimates

Primary ReceiverPrimary Receiver

Interface ProcessorInterface Processor

Dual Freq. ANTDual Freq. ANT


SSLIDELIDE 2424JAXA-ENRI Interface (G-ICD)JAXA-ENRI Interface (G-ICD)

• Ground System ICD (Interface Control Document)Ground System ICD (Interface Control Document)::– Defines interface between JAXA QZSS MCS and ENRI L1SMS;Defines interface between JAXA QZSS MCS and ENRI L1SMS;– First issue: Jan. 2008;First issue: Jan. 2008;– Specifies data stream on TCP/IP connection bit-by-bit.Specifies data stream on TCP/IP connection bit-by-bit.

• Dual communication lines for redundancyDual communication lines for redundancy::– ISDN (64kbps) and optical (1.5Mbps) links;ISDN (64kbps) and optical (1.5Mbps) links;– Low-rate ISDN: Reliable transmission for uploading L1-SAIF message;Low-rate ISDN: Reliable transmission for uploading L1-SAIF message;– High-rate optical link: Exchange station status and monitor station observation;High-rate optical link: Exchange station status and monitor station observation;– Only for the experiment; no definition of service levels.Only for the experiment; no definition of service levels.

L1SMSL1SMS

MCS AMCS A

MCS BMCS B

RouterRouterRouterRouter


ISDNISDN

OpticalOptical

Upload MessageUpload Message

Other DataOther Data

JAXAJAXAENRIENRI


SSLIDELIDE 2525JAXA-ENRI Interface (G-ICD)JAXA-ENRI Interface (G-ICD)

Packet ID Contents Direction Link Interval

0xC0 Upload Message L1SMS -> MCS ISDN 1 s

0xC1 Upload Message Echo L1SMS <- MCS ISDN 1 s

0x02 SMS Status L1SMS -> MCS Optical 5 s

0xE2 GPS/QZS Observation L1SMS <- MCS Optical 1 s

0xE4 GPS Observation L1SMS <- MCS Optical 1 s

0xE1 Monitor Station Status L1SMS <- MCS Optical 5 s

0x11 Telemetry Command L1SMS <-> MCS Optical N/A

0x12 Telemetry Data L1SMS <- MCS Optical min 1 s

0x01 Experiment Status L1SMS <- MCS Optical 10 s

0x21 Orbit and Clock L1SMS <- MCS Optical 30 s


SSLIDELIDE 2626Closed-Loop Interface TestClosed-Loop Interface Test

• Interface test between JAXA MCS and ENRI L1Interface test between JAXA MCS and ENRI L1SMS and between Nav payload and receiver;SMS and between Nav payload and receiver;

• Checked the format of transmitted and received Checked the format of transmitted and received data packets, then compared log files bit-by-bit;data packets, then compared log files bit-by-bit;

• Successfully completed in Dec. 2008.Successfully completed in Dec. 2008.

HUBHUBLANLAN

Upload MessageUpload Message JAXAJAXAENRIENRI

LogLogLogLog

MCS BMCS B

NavigationNavigationPayload EMPayload EM

RF CableRF CableL1-SAIF SignalL1-SAIF Signal

L1SMSL1SMSSimulatorSimulator

HUBHUB

NEC (Fuchu, Tokyo)NEC (Fuchu, Tokyo)

LogLog


L1SMS SimL1SMS Sim

Nav payloadNav payload

ReceiverReceiver


SSLIDELIDE 2727JAXA-ENRI Interface TestJAXA-ENRI Interface Test

• Interface test between two facilities, JAXA MCS and ENRI L1SMS, with the complete Interface test between two facilities, JAXA MCS and ENRI L1SMS, with the complete configuration of communication lines;configuration of communication lines;

• Confirmed the format of transmitted and received data packets, then compared log Confirmed the format of transmitted and received data packets, then compared log files taken at both facilities bit-by-bit;files taken at both facilities bit-by-bit;

• Successfully completed in Jan. 2010.Successfully completed in Jan. 2010.

L1SMSL1SMSSimulatorSimulator



ISDNISDN

OpticalOptical

Upload MessageUpload Message

Other DataOther Data

JAXAJAXAENRIENRI

LogLog LogLog

MCS AMCS A

MCS BMCS B

ENRI (Chofu, Tokyo)ENRI (Chofu, Tokyo) JAXA (Tsukuba)JAXA (Tsukuba)


SSLIDELIDE 2828

Part 4Part 4

Realtime Operation TestRealtime Operation Test


SSLIDELIDE 2929Realtime Operation TestRealtime Operation Test

• Tested performance of the ICP Tested performance of the ICP Implemented as a subsystem of Implemented as a subsystem of L1SMS; running with L1SMG;L1SMS; running with L1SMG;

• Analyzed user position error at 14 Analyzed user position error at 14 evaluation locations; Numbered from evaluation locations; Numbered from North to South;North to South;

• Used GEONET stations as all Used GEONET stations as all monitor stations and evaluation sites.monitor stations and evaluation sites.

GMS Stations (6) for L1SMGGMS Stations (6) for L1SMG

L1-SAIF Experimental AreaL1-SAIF Experimental Area

IMS Station (200) for ICPIMS Station (200) for ICP

Evaluation Locations (14)Evaluation Locations (14)


SSLIDELIDE 3030Results – Position Error SampleResults – Position Error Sample

• Example of user positioning error at Site Example of user positioning error at Site #5 93022 Choshi (East of Tokyo);#5 93022 Choshi (East of Tokyo);

• ICP: 200 IMS, 5-deg IGP, 0th Order Fit;ICP: 200 IMS, 5-deg IGP, 0th Order Fit;

• Period: 16-21 Jan. 2009 (5 days).Period: 16-21 Jan. 2009 (5 days).

MSAS AugmentationMSAS Augmentation

Standalone GPSStandalone GPS

L1-SAIF AugmentationL1-SAIF Augmentation

SystemHorizontal

ErrorVertical Error

L1-SAIFRMS 0.23 m 0.36 m

MAX 1.67 m 3.35 m

MSASRMS 0.46 m 0.59 m

MAX 1.73 m 2.43 m

Standalone GPS

RMS 1.25 m 2.99 m

MAX 4.30 m 8.11 m


SSLIDELIDE 3131Location vs. Horizontal AccuracyLocation vs. Horizontal Accuracy

• ICP improves position accuracy in the Southern Region;ICP improves position accuracy in the Southern Region;• First order estimation is better to ensure accuracy.First order estimation is better to ensure accuracy.


SSLIDELIDE 3232Location vs. Vertical AccuracyLocation vs. Vertical Accuracy

• 1 meter accuracy is achievable even for vertical direction;1 meter accuracy is achievable even for vertical direction;• Note that these results associate with solar minimum phase.Note that these results associate with solar minimum phase.


SSLIDELIDE 3333Realtime Operation Using GEORealtime Operation Using GEO

• ETS-VIII satelliteETS-VIII satellite::– Engineering Test Satellite for mobile communication and onboard clock of Engineering Test Satellite for mobile communication and onboard clock of

navigation-grade;navigation-grade;– Geostationary satellite with very largeGeostationary satellite with very large

(19m) folding antenna;(19m) folding antenna;– Launched in Dec. 2006 by JAXA.Launched in Dec. 2006 by JAXA.

• ENRI joined the experimentENRI joined the experiment::– Communication experiment betweenCommunication experiment between

two fixed points;two fixed points;– L1SMG transmitted L1-SAIF messageL1SMG transmitted L1-SAIF message

to ETS-VIII;to ETS-VIII;– Received L1-SAIF message was inputReceived L1-SAIF message was input

to the GPS/L1-SAIF receiver andto the GPS/L1-SAIF receiver and

processed properly;processed properly;– Successfully completed in Feb. 2009.Successfully completed in Feb. 2009. ETS-VIII SatelliteETS-VIII Satellite


SSLIDELIDE 3434Uplink from TokyoUplink from Tokyo

L1-SAIF Master StationL1-SAIF Master Station

ETS-VIII SatelliteETS-VIII SatelliteEthernetEthernet

ETS-VIII Terminal EquipmentETS-VIII Terminal Equipment

RF signalRF signal

SATCOM AntennaSATCOM Antenna

L1-SAIF messageL1-SAIF message


SSLIDELIDE 3535Downlink to SendaiDownlink to Sendai


ETS-VIII Terminal EquipmentETS-VIII Terminal Equipment

SATCOM AntennaSATCOM Antenna

ETS-VIII SatelliteETS-VIII Satellite

RF signalRF signal EthernetEthernet

GPS signalGPS signalL1-SAIF messageL1-SAIF message

(400km away from Tokyo)(400km away from Tokyo)


SSLIDELIDE 3636L1-SAIF Receiver OutputL1-SAIF Receiver Output

2009/2/17 01:21:39 to 07:23:14 (6 hours)2009/2/17 01:21:39 to 07:23:14 (6 hours)

Standalone GPSStandalone GPS L1-SAIF AugmentationL1-SAIF Augmentation

H Error RMS = 0.412mH Error RMS = 0.412mV Error RMS = 0.464mV Error RMS = 0.464m

H Error RMS = 1.221mH Error RMS = 1.221mV Error RMS = 4.043mV Error RMS = 4.043m


SSLIDELIDE 3737Stability TestStability Test

• Runs L1SMG for several monthsRuns L1SMG for several months::– To investigate stability of the software implemented in L1SMG;To investigate stability of the software implemented in L1SMG;– Period I: 2008/3/11 to 2008/5/24 (74 days);Period I: 2008/3/11 to 2008/5/24 (74 days);– Period II: 2008/6/10 to 2008/8/28 (79 days).Period II: 2008/6/10 to 2008/8/28 (79 days).

• Result: No major trouble:Result: No major trouble:– The software runs for the periods without human interaction;The software runs for the periods without human interaction;– User position accuracy was reasonable.User position accuracy was reasonable.

Site940030

Oga

93101

Omaezaki

940058

Takayama

940085

Tosashimizu

950491

Sata

Period IHor 0.362 0.363 0.362 0.423 0.502

Ver 0.517 0.536 0.548 0.608 0.739

Period IIHor 0.460 0.440 0.347 0.416 0.552

Ver 0.657 1.236 0.678 0.699 1.371

Resulted User Position Accuracy at Some Locations [unit: m]Resulted User Position Accuracy at Some Locations [unit: m]


SSLIDELIDE 3838ConclusionConclusion

• ENRI has been developing L1-SAIF signalENRI has been developing L1-SAIF signal::– Signal design: GPS/SBAS-compatible;Signal design: GPS/SBAS-compatible;

– Implemented L1-SAIF Master Station (L1SMS) which generates augmentation messImplemented L1-SAIF Master Station (L1SMS) which generates augmentation message stream in realtime and transmit it to QZSS MCS.age stream in realtime and transmit it to QZSS MCS.

• Completed, so farCompleted, so far::– Design of L1-SAIF signal and publishing as a part of IS-QZSS;Design of L1-SAIF signal and publishing as a part of IS-QZSS;

– Development of GPS/L1-SAIF simulator and receiver;Development of GPS/L1-SAIF simulator and receiver;

– Development of G-ICD between L1SMS and QZSS MCS, and interface test of them;Development of G-ICD between L1SMS and QZSS MCS, and interface test of them;

– Interface test at the closed-loop configuration including L1SMS, MCS, QZSS navigatInterface test at the closed-loop configuration including L1SMS, MCS, QZSS navigation payload, and GPS/L1-SAIF receiver;ion payload, and GPS/L1-SAIF receiver;

– Realtime operation test with/without geostationary satellite (ETS-VIII); andRealtime operation test with/without geostationary satellite (ETS-VIII); and

– Stability test of L1SMS.Stability test of L1SMS.

• Currently working forCurrently working for::– Final interface test at the full-configuration of ground/space systems;Final interface test at the full-configuration of ground/space systems;

– Preparation of performance experiment with the first QZS space vehicle.Preparation of performance experiment with the first QZS space vehicle.

t. sakai, s. fukushima, and k. ito electronic navigation research institute, japan t. sakai, s....

Documents

l1saif signal

l1saif master station

enri s lide

overview of qzss program

qzss mcs

frequencies l1 ca

l1 single frequency

navigation services