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Proddage Generic Material. Types of Navigation. Celestial The use of the stars, sun and time to calculate positions Radio Navigation Land based e.g. Loran C Satellite Based e.g. GPS. History of Satellite Navigation. TRANSIT / TSIKADA DNSS Timation System 621B NAVSTAR GPS GLONASS. GPS.
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Types of Navigation • Celestial • The use of the stars, sun and time to calculate positions • Radio Navigation • Land based e.g. Loran C • Satellite Based e.g. GPS
History of Satellite Navigation • TRANSIT / TSIKADA • DNSS • Timation • System 621B • NAVSTAR GPS • GLONASS
GPS • Multiple series of satellites provide the current constellation • Newer satellites have better clocks and are able to continue operating automatically without contact from the ground stations • Continual replenishment of the satellites is ongoing
GPS Current Status • Full constellation in operation • Continuing replenishment of old satellites • Some satellites have lasted well outside of their design life
GLONASS • Russian global satellite navigation system • Very similar to GPS concept • Full Constellation expected in 2007
GLONASS Current Status • GLONASS programme to continue • Replenishment of satellites is underway • Future of the system is assured for military and civilian purposes
GPS / GLONASS Initial Design Differences
Current Use of Satellite Navigation • Markets • Aviation • Maritime • Road • Rail • LBS • Professional
Space Based Augmentation Systems WAAS EGNOS MSAS
US - WAAS • Designed for Aviation Industry • Enhanced Accuracy, Integrity and Continuity • Initial Operating Capability (IOC) July 2003
India - GAGAN • GPS and GEO Augmented Navigation • 1 Geostationary Satellite • India based GroundReference Stations • Interoperability with EGNOS, MSAS & WAAS
EGNOS • ESA • System Design • Development • Qualification & Technical Validation • European Commission • Land User Requirements • Satellite Communications • User Equipment • EUROCONTROL • Civil Aviation Requirements • Operational Testing and Validation
EGNOS System Architecture Satellites: Geostationary, GPS & GLONASS 7 NLES 4 MCC 34 RIMS Users
EGNOS Ground Segment MCC RIMS NLES
EGNOS Measured Accuracies (Sept 5 2004) • Recorded over a 24h period • Less than 1m horizontal accuracies recorded • Vertical accuracies of 1-2m (well below the 7.6m specification
EGNOS Message Server • 24h/24h Archive of EGNOS Messages • Broadcast messages are stored in hourly text files • New Possibilities • Evaluation of EGNOS performance • Assessment of EGNOS at IGS Sites • Able to post process data with conventional GPS receivers • Test EGNOS enabled receivers
EGNOS - Extensions • Initial MRD developed in 1998 • New Developments in the GNSS Industry • Galileo • GPS Modernisation • New Signals • Launch of WAAS • EGNOS V2 Concept Developed
EGNOS Evolution Plans • Three EGNOS Versions conceived in 2005-2008 Step 1 Step 2 EGNOS v2.1 End 2006 EGNOS products over non-GEO data links (INSPIRE) Extension to MEDA and East of Europe Message Type 02 Extension EGNOS v2.2 End 2007 EGNOS MT 28 Extension in Africa Modernised RIMS receivers SAR return link EGNOS v2.3 End 2008 L5 standards and L5 GEO broadcast L1/L5/Galileo enhanced RIMS receivers
EGNOS & Galileo • First steps for Europe in the field of satellite navigation • Precursor to Galileo • Allows early application development • Testing of prototype business models and concepts
Shortfalls & Limitations • Interference • Jamming • Accuracy • Integrity • Availability • Multipath • Power
Technical Issues • Geometry • Current Systems • Galileo Good Geometry Bad Geometry
Operational Issues • Availability • Blocked Signals • Urban Areas • Trees • Underground • Continuity
Safety Issues • Receiver Autonomous Integrity Monitoring (RAIM) • Ground Integrity Channel (GIC) • Backup Systems • Common Mode
Regulatory Issues • Applied for GNSS use in safety applications • MUSSST Study • Methods to authorise for operational use • Specification of validation procedures • Safety case approach
Legal Issues • Privacy Concerns • Data Protection • Evidence • Time Stamping
Other Positioning Methods & Enhancements • Other methods of positioning that can be combined with GNSS are as follows: • Pseudolites • Terrestrial Radio Navigation • Mobile Telecommunication Positioning • Other Sensors
Pseudolites • Ground Based “Satellites” • GPS-like signals • Provide additional ranges to enhance positioning in difficult operating environments
eLoran (Terrestrial System) • Alternative Positioning method to GPS • eLoran incorporates the latest: • Receiver • Antenna • Transmission Technology • Enhanced systems can now provide accuracies of 8-20m
Mobile Phone Positioning • For use in the provision of Location Based Services • Network Based Solutions • PDE • Angle of Arrival • Time of Arrival • Handset Based Techniques • SIM • E-OTD
Other Systems • Gyrocompass • Inertial Measurement Units • Magnetometers • Digital Map • Digital Elevation Model • Radar etc.
GPS III • Enhance the overall GPS system • Continuing development in response to military and civilian needs • Enhanced Anti-Jam Capabilities • Improved security, accuracy and reliability
Future GLONASS • GLONASS K • Integrity • Search and Rescue • Modernisation of Russian Geodetic Network • India may become a partner in the future of the GLONASS programme
QZSS • QZSS will bring “Value added services for mobile users by combining communications, broadcasting, and positioning. Nationwide coverage is available since the QZSS is directly overhead.“