Prof. dr. sc . Ivan Markežić ivan.markezic@fpz.hr

1. Универзитет „Св. Климент Охридски“ Технички Факултет – БИТОЛА МУЛТИРАТЕРАЦИЈА КАКО ТЕХНИКА НАКОНТРОЛА НА ВОЗДУШНИОТ СООБРАЌАЈMULTILATERATION AS SURVEILLANCE CHOICE Prof. dr. sc. Ivan Markežić ivan.markezic@fpz.hr MULTILATERACIJA KAO TEHNIKA KONTROLE ZRAČNOG PROMETA

2. Content Air Traffic Surveillance – Techniques and Technologies Multilateration System Description Multilateration in an ECAC Context Conclusion

3. ”In The Beginning” atc6.AV

4. Air Traffic Surveillance – Techniques and Technologies

5. Air Traffic Surveillance – Techniques and Technologies Principle of Multilateration

6. Air Traffic Surveillance – Techniques and Technologies • Surveillance strategy: - mutually interoperable and compatible technologies MSSR/SSR Mode S ADS-B Multilateration, WAM

7. MLT System Description • Principle of Multilateration multilat_princip.avi

8. MLT System Description • Principle of Multilateration Co-operative Independent Surveillance -a number of antennas receive a signal from an aircraft - central processing unit calculates the aircraft’s position from the time difference of arrival (TDOA) of the signal at the different receivers - the TDOA between two antennas corresponds with a hyperboloid, a 2D surface in a 3D space - at least four antennas are required for a 3D position calculation - if altitude is known already, three antennas are sufficient

9. MLT System Description • Active and Passive WAM System Passive WAM Systems No transmitter means: - No transmitter license - No 1030 spectrum usage - No increase to 1030/1090 SSR environment (FRUIT) Aircraft detection requires: - The aircraft is Mode S equipped or - The aircraft is within existing MSSR coverage

10. MLT System Description • Active and Passive WAM System Active WAM Systems Independent of existing infrastructure -Improveddetection of Mode A/C only aircraft Simpler and cheaper than MSSR interrogator - Fixed antenna -Low power interrogation option Suitable for Mode S Surveillance Care must be taken not to generate excess 1030/1090MHz FRUIT

11. MLT System Description • WAM performance Multilateration and Wide Area Multilateration Multilateration - Independent cooperative surveillance Surface Multilateration - Tracks aircraft on the surface -Uses 2D algorithms Wide Area Multilateration - Tracks aircraft in flight -Uses 3D algorithms

12. MLT System Description • WAM performance • (en route application) MSSR WAM A 5 receiver WAM system with a 60nm baseline gives: - Higher accuracy than MSSR - Reduced range due to horizon effect

13. MLT System Description • WAM performance • (en route application) A 9 receiver WAM system with a 60nm baseline gives: - Higher accuracy than MSSR - Similar range to MSSR Horizon effect (WAM horizon is the horizon of multiple sites)

14. MLT System Description • WAM performance • (TMA application) Coverage at 3000ft : - Larger baselines give better accuracy Shorter baselines give better low level coverage

15. MLT System Description • Impact on existing ATM operations There is no negative impact on existing ATM operations -WAM systems can easily be integrated into current ATM architectures -WAM systems can exceed the performance of existing surveillance sensors -There need be no difference in the information presented to the controller WAM systems could provide benefits to ATM operations in the future -WAM systems are capable of higher accuracies than current sensors -WAM systems are capable of higher update rates than current sensors -WAM systems can measure geometric height in addition to receiving pressure altitude

16. Multilateration in an ECAC Context • Eurocontrol is promoting WAM technology for ATCsurveillance: • (relatively low cost and good performance) Ground based surveillance infrastructure for En-Route and TMA

17. Multilateration in an ECAC Context Surveillance Strategy at the Aerodrome ADS-B/WAM Combination - future surveillance scenario (!?)

18. Conclusion • WAM systems are potentially capable of significantly higher accuracies than an equivalent radar service: • a five receiver WAM system has a higher accuracy than MSSR • (both an en-route and terminal ) • The range is lower due to the horizon of multiple receivers • A comparable range can be achieved by adding in additional receivers • En-route WAM systems can also provide accurate height measurement • information • All current WAM systems are based on 1090 MHz technology because: • wide availability of the technology as part of the airborneinfrastructure • The properties of these signals for use in a WAM system • (aircraft identification and accurate TDOA measurements) Provide ADS-B data in addition to independent position Do not require additional avionics Ref.: The ATM Surveillance Strategy for ECAC, 2.2, ed. date 07/04/2008. http://www.eurocontrol.int/surveillance/gallery/content/public/documents/WAM_study_report_1_1.pdf

19. ВИ БЛАГОДАРАМ НА ВНИМАНИЕТО