On October 23rd, 2014, we updated our
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Limitations of GNSSLimited or no service in: Susceptible to:• Urban/Natural Canyons • Interference• Vegetated Areas • Intentional Jamming• Indoors • Spoofing• Underground • Space weather events• Underwater • Military motives• High levels of radio • Non-Australian decision frequency interference makers
Dependence and Vulnerability• Global Navigation Space Systems: reliance and vulnerabilities (The Royal Academy of Engineering)• Mid-term review of European satellite radio navigation programmes (European Commission)• NSTAC Report to the President on Commercial Communications Reliance on the Global Positioning System (National Security Telecommunications Advisory Committee)• Australian Strategic Plan for GNSS (Australian Spatial Consortium• ...
AlternativesRevert back to old Adopt new technology, butmethods? it would need to:• Norm for most NSW surveyors • Work in real-time • Achieve cm level accuracy in national coordinate system • Integrate with other sensors and systems
Sydney Satellites• World first test of the performance of Locata vs GNSS in a maritime environment. Collaborative partners:• Observed by Australian Hydrographic Service (RAN)
What is Locata?Ground based positioning system consisting of:• Four or more ‘LocataLites’ (shown in picture) which synchronise with each other using TimeLoc• LocataLites can be set up on existing control or surveyed in• Locata rover(s) roaming within bounds of LocataLites
ObjectivesQuickly establish a temporary Locata network in a harbour/maritime scenarioDetermine the position for a vessel moving within the network using Locata technologyEvaluate the performance of Locata compared to existing positioning techniques (GNSS)
Preparation WorkIn the lead up to the final test day:• Multiple reconnaissance trips• Stakeholder meetings• UNSW practice day• Signal test day• UNSW/Locata training day• Preliminary positioning test day
Example Test Run Fort Denison CORS
Set-Up on Sydney Ports Corp. Vessel Locata Receiver TemporaryAntenna Mount
Antennas Locata Helix Locata 5/8 Wave Test GPS Test GPSSPC GPS SPC GPS
Preliminary Results• Analysis of three runs of Farm Cove• Approximately 12 minutes of data• LocataLites ‘in view’ ranges from 4 up to 7 during this particular session• Data collected at 10Hz (both GPS and Locata)• Compared to GPS RTK solution after offsets taken into account
Comparison to high-precision GPS. 2D RMS Error (95%) Horizontal: 4.4 cm
Outcomes Quickly establish a temporary Locata network in a harbour/maritime scenario Determine the position for a vessel moving within the network using Locata technology Evaluate the performance of Locata compared to existing positioning techniques (GNSS)
Next phase of testing• Emergency Services Applications – Urban environments/Indoors – Barangaroo development or Australian Technology Park possible locations• Port Logistics• National Positioning Infrastructure – Where does it fit? – Enable navigation through virtual world