gnss systems status and technical updates · / presented by: john vint survey manager fugro survey...

www.fugro.no / www.starfix.com

Presented by: John Vint Survey Manager Fugro Survey AS The Hydrographic Society in Scotland, 27th March 2013

GNSS SYSTEMS STATUS AND TECHNICAL UPDATES


Scope of Presentation

GNSS System Status.

Solar Activity.

Challenges of “The Arctic”.

Precise Remote Tracking.

Galileo Positioning.


Galileo, European Satellite Navigation System

Galileo System Testbed 2 test satellites

In-Orbit Validation (IOV) 4 fully operational satellites

and ground segment

Initial Operational Capability (IOC) Early Services for Open Service

Demonstrator for Commercial Service

2005/2008

2011/2013

2014/2016

Full Operational Capability All services, 30 satellites

2020

Full Galileo Constellation

http://images.google.co.uk/imgres?imgurl=http://www.giove.esa.int/images/mainpage/GIOVE_Logo.jpg&imgrefurl=http://www.giove.esa.int/index.php?menu=1&h=516&w=420&sz=67&hl=en&start=5&tbnid=xfgIAALy1g8aBM:&tbnh=131&tbnw=107&prev=/images?q=giove&gbv=2&svnum=10&hl=en

http://images.google.co.uk/imgres?imgurl=http://www.esa.int/images/GSTB_V1_logo_120.jpg&imgrefurl=http://www.esa.int/esaNA/SEMM9GRMD6E_galileo_2.html&h=120&w=98&sz=15&hl=en&start=1&tbnid=-GqYg-KeJUOkNM:&tbnh=88&tbnw=72&prev=/images?q=gstbv1&gbv=2&svnum=10&hl=en&sa=G


Galileo Services Provision Time Line


October 2011 and October 2012 a total of four satellites launched – Navigation message transmitted on four IOV satellites

mid-March 2013, first Galileo only positioning

All industrial contracts necessary to ensure early Galileo services have been signed (16 satellites)

To accelerate Galileo’s deployment the following contracts were signed on 2 February 2012: – Additional order for 8 satellites – Adaptation of Ariane-5 for Galileo (launch of 4 satellites) – Booking of one Ariane-5

Galileo Summary


• Regional Asia coverage 2013 – 4 MEO (Medium Earth Orbit) – 5 GEO (Geostationary Orbit) – 5 IGSO (Inclined Geostationary Orbit)

• Navigation message definition released

Dec 2012 (only Chinese companies had access earlier)

• Full world wide Coverage 2020

• 30 MEO: 21500 km, 55 deg inclination

• 5 GEO: 35786 km

BeiDou, Chinese Satellite Navigation System

http://www.oosa.unvienna.org/oosa/en/SAP/gnss/icg/icg06/sixth-icg-meeting_-online-presentations.html


GPS/GLONASS

GLONASS 24 Operational satellites GLONASS-K next generation with CDMA

(Code Division Multiple Access, all satellites transmit on the same frequency, as GPS/Galileo/Beidou)

GPS 32 operational satellites Launching GPS IIF satellites (with L5) GPS III with new L1C from 2015


Solar Activity

Auroral Oval


Solar Cycle 24:

Start: 2009

Maximum: 2013

http://solarscience.msfc.nasa.gov/images/ssn_predict_l.gif

Solar Cycle 24


http://online.qmags.com/GNSS0709/Default.aspx

100 days / year

10 days / year

Scintillation Frequency at Solar Maximum


Challenges of “The Arctic”


L-Band Delivery Satellite Footprints


AORE ESAT

IOR

Shtokman 73N,45E

L-Band Coverage ESAT, AORE & IOR


ASAT

AORW

L-Band Coverage ASAT & AORW


AUSAT PORL

ASAT

L-Band Coverage ASAT, PORL & AUSAT


Improved L-Band Delivery

Spot Satellite Delivery

Customer Terminal

Fugro Commissioned Alison AD-492 and AD-493 Antennae


Iridium Summary

Using the Iridium low orbit satellite communication system provides coverage at high latitudes.

Iridium Open Port provides access to the Internet, it is not a broadcast. Daily costs apply.

Availability when accepting correction age up to 2.5 minutes is above 98%

Average outage time is below 5 minutes.

Fugro have had 4 systems deployed during the summer 2012 – West of Greenland.


Iridium System

• “Iridium Next” satellites to be built by Thales Alenia Space France.

• Launches 2015-2017 • 70 satellites in 10 launches

• Iridium consists of 66 low orbit satellites, with orbit height 780 km (100 min period).

• Satellite weight 680 kg 5-7 satellites launched with one booster

• Polar coverage.

• Launched 1997-1999


Iridium System


Iridium Data Transfer Process

NTRIP Caster Perth / Oslo

Open Internet

Iridium Gateway

To / From Iridium Satellites

Network Control

Offshore Installation

Open Port Terminal

PC NTRIP Client

Fugro Software

Connection to Open Internet is established by onboard PC


Starfix.G2 Performance in Tromsø (70°N)


Starfix.G2 Performance in Longyearbyen (78°N)


• Test Vessel • Atlantic Guardian • Operated by EMGS (http://www.emgs.com) • Electromagnetic Survey

Case Study – Atlantic Guardian


Test Equipment

•Test Equipment

• Kongsberg Seatex Seapath (DGNSS and MRU Inertial System) • Fugro G2 GPS/GLONASS orbit/clock corrections received in 3610 demodulator.

Open Internet Connection

Iridium Below Deck Equipment.

Above Deck Equipment. (11 kg)

Seastar 3610. Kongsberg Seatex Seapath.

Possible L-Band Broadcast Antenna


Availability of Corrections

• Availability is shown when accepting a correction age of 2.5 minutes and when accepting a correction age of 4.5 minutes.

• August data has higher availability, except for two days when two incidents of 20-30 minute outage.

• A typical maximum age of corrections used offshore is 1 Minute. The reduced accuracy due to this is marginal.


Availability of Corrections

• Availability is shown when accepting a correction age of 2.5 minutes and when accepting a correction age of 4.5 minutes. • A typical maximum age of corrections used offshore is 1 Minute. The reduced accuracy due to higher age of corrections is marginal.


Outage Times

• Maximum outage period in March was about 10 minutes

• In the August data the there was two outages in the 20-30 min range in 12 days.

• The mean outage period is below 10 minutes.


Outage Times

• In the 12 day data set the there was two outages in the 20-30 min range (one of them due to Ntrip Caster downtime in Perth Network Control Centre).

• The mean outage period is below 10 minutes.

The 13 Aug 27 min outage was due to Ntrip Caster downtime


Atlantic Guardian 2012 in the Barents Sea

Data collected at about 73 deg North in the Barents Sea

Reported Standard Deviation Height (how accurate does the system think the height is)

Relative Height

Age of Correction

-1.5 m

1.5 m

5.0 min

Time UTC 00:00 24:00

2.5 min

0.0 min

Age of Correction indicates how long ago since the last set of G2 corrections were received via Iridium

12:00


Starfix.G2 Errors with “High Age of Corrections”

Height error

Age of Correction

Time UTC

12:00 15:00 14:00 13:00

East error

North error

-0.3 m

0.3 m

5.0 min 2.5 min

0.0 min

-0.3 m

0.3 m

-0.3 m

0.3 m

95% Horizontal during high age period: 11 cm


Starfix.G2 Errors without “High Age of Corrections”

Height error

Age of Correction

Time UTC

12:00 15:00 14:00 13:00

East error

North error

-0.3 m

0.3 m

5.0 min 2.5 min

0.0 min

-0.3 m

0.3 m

-0.3 m

0.3 m

95% Horizontal during high age period: 4 cm


Summary of Iridium Testing

Using the Iridium low orbit satellite communication system provides coverage at high latitudes.

Iridium Open Port provides access to the Internet, it is not a broadcast service. Daily costs apply. 2.5-3.5 MByte per day.

Availability when accepting correction age up to 2.5 minutes is typically 97-99%

Average outage time is below 5 minutes.

G2 via Iridium is an operational service (being used on several vessels at high latitude)


Precise Remote Tracking


Advanced Gun Float and Tailbuoy Tracking

StarTrack Remote Unit (SRU)

StarTrack Vessel Control Unit (VCU)

System Precision: RTK – 3 cm 1 Sigma PPP – 10 cm 1 Sigma


StarTrack Remote Unit (SRU): One pod design. Trimble GNSS Card GPS (L1/L2/L2c) and GLONASS

(L1/L2). Computations undertaken in Pod Results and QC sent to vessel.


RTK baseline calculations between vessel and pod: – Accuracy 3 cm 1 Sigma.

PPP solution for each pod – Excellent QC: – Accuracy 10 cm 1 Sigma.

Programming of Pods via wireless hand held terminal. Mounting and installation compatible with Seatrack. Fully ROHS / CE Compliant and NLR shock tested.


StarTrack Vessel Control Unit (VCU): 2U 19” Rack Mounted. Full StarPack Functionality. Extended Functionality for StarTrack. Place for up to 8 radio telemetry systems. Communication between SRU and client software. Supports all current RGNSS Outputs.


StarTrack FAT Results – 2 Hz Update


StarTrack FAT Results – ½ Hz Update


Precise Remote Positioning – Other Uses

System designed for Seismic Gun and Tailbuoy Tracking, but other uses are: – General Remote Tracking.

– Dynamic Calibration.

– Relative Leg Penetration on Jack-up Rigs.

– Precise vessel draught measurements for use with

GNSS tides.


Real-time PPP with Galileo is a “Reality”

Fugro have been working on a computing Galileo orbit and clock corrections from our reference station network.

Navigation Message enabled on the 4 IOV satellites in March 2013.

Within one week of activation, Fugro had an operational Galileo PPP service.

Noise levels on Galileo solution is less than on the combined GPS/GLONASS/Galileo solution.

See also http://gpsworld.com

http://gpsworld.com/


Galileo PPP System Performance


Thank you. Questions ?

gnss systems status and technical updates · / presented by: john vint survey manager fugro survey...

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