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ADS-B Technology Overview. Marc Ramsey marc@ranlog.com PASCO Safety Seminar Oakland, California November 4, 2006. Topics. What is ADS-B? How Does ADS-B Work? Why Ground Stations? Broadcast Services Current Continental US ADS-B Coverage Expanded Coverage: 2008 to 2010?
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ADS-B Technology Overview Marc Ramsey marc@ranlog.com PASCO Safety Seminar Oakland, California November 4, 2006
Topics • What is ADS-B? • How Does ADS-B Work? • Why Ground Stations? • Broadcast Services • Current Continental US ADS-B Coverage • Expanded Coverage: 2008 to 2010? • Universal Access Transceivers • Will ADS-B Replace Transponders? • Why Should We Care? • What Can We Do?
What is ADS-B? • Automatic • Periodically transmits information with no pilot or operator input • Dependent • Position and velocity data derived from Global Positioning System (GPS) • Surveillance • Determines position of aircraft, vehicles, or ground obstructions • Broadcast • Transmitted data available to anyone with appropriate receiving equipment
How Does ADS-B Work? • ADS-B transmitter periodically transmit: • Unique identifier • 3D Position and velocity vector from GPS • Altitude from pressure sensor and/or GPS • ADS-B receiver receives: • Data from nearby ADS-B transmitters • Traffic and weather data from ground stations • ADS-B transceiver transmits and receives • Two types of ADS-B devices • Mode S/ES (Extended Squitter) at 1090 MHz • UAT (Universal Access Transceiver) at 978 MHz • Intended for General Aviation use
Why Ground Stations? • Receive position/velocity data from ADS-B (both UAT and S/ES) equipped aircraft • Pass received data to ATC system • Obtain traffic data from ATC system for other ADS-B and transponder equipped aircraft • Broadcast composite traffic data • Broadcast weather and airspace data • Each station has a range of 100 to 150 miles
Who Can See Who? GSGround Station SSRSecondary Surveillance Radar
Broadcast Services: TIS-B • Traffic Information Service • Provides real-time position reports • ADS-B equipped aircraft • Mode B/C equipped aircraft from secondary surveillance radar data
Broadcast Services: FIS-B • Flight Information Service • National Weather Service products • NEXRAD • Special use airspace • Temporary flight restrictions (TFRs)
Universal Access Transceiver • Transmits current state vector(3D position/velocity) once per second • Receives TIS-B and FIS-B • Low transmit power requirements • Low power (limited to 18,000 feet) 7 to 18 watts • Medium power (no alt. Restriction) 16 to 40 watts • Short transmit duty cycle (0.03%) • Garmin GDL 90 • Only UAT currently certified • $8000 without display • $16,500 with color display
Will ADS-B Replace Transponders? • Short answer: eventually… • Most air transport aircraft equipped by 2020 • Most other aircraft equipped by 2030 • Advantages • Precise position data on all aircraft in ATC system • UAT transceivers will eventually be smaller, lighter, and use less current than Mode C • ADS-B ground stations less expensive and cover wider area than primary/secondary radar systems • What’s holding it up? • Lack of integration with TCAS • Lack of ground stations
Why Should We Care? • Potential benefits • Allow gliders, paragliders, hangliders, etc. to be fully integrated into future ATC system • Ultimately much lower power requirements than existing Mode C or S transponders • Integrated collision avoidance • Real-time glider tracking for contests, etc. • Potential Issues • Short term lack of suitable units • Competition • UAT equipped gliders can be tracked by competitors • Weather data available to UAT equipped competitors
What Can We Do? • Push for short term installation of ground station in Reno area • Propose pilot program involving subsidized installation of UATs in Reno area gliders • Ask for waiver allowing occasional use of low power UATs in wave windows • Can we interest someone in developing low cost, low power UAT using PDA as display? • Other ideas?
Winch Launch Update • Recent trip to UK • Lasham • Bicester • Cambridge • Remember to get your medical form • BGA transition training • 2 to 4 normal launches • 2 high failures • 2 medium failures • 2 low failures • Any interest? • Contact me