%0 Generic %1 sonnleitner2023airspace %A Sonnleitner, Clemens %A Hobiger, Thomas %D 2023 %K %T Airspace Surveillance with Unsynchronized low-cost ADS-B Receivers using Time Difference of Arrival Observations %X Safe operations and efficient usage of the available airspace require precise air traffic surveillance. Classic radar systems are more and more replaced by Automatic Dependent Surveillance - Broadcast (ADS-B) which provides a higher update rate, lower operational cost and better accuracy for cooperative aircraft. Since the end of 2020 ADS-B transmitters are mandatory for a large portion of commercial aircraft in the European airspace, raising the amount of performed flights with ADS-B to 94%. As such signals are received by several ground-stations, their reception times can be used to perform multilateration in order to determine the position of the transmitter without relying on the content of the ADS-B message which can be faulty or manipulated. However, multilateration approaches require precise time synchronization among the ground stations. The synchronization of ADS-B receivers spread over a large area is complex and requires additional hardware. Therefore, we developed a passive Time Difference Of Arrival (TDOA) multilateration approach for which clocks only need to be roughly synced (e.g. using the Network Time Protocol which achieves time synchronization in the range of 10ms). In our approach the TDOA data is fed into an extended Kalman Filter which estimates relative clock offsets of all ground stations as well as positions and velocities of all aircraft from which ADS-B data were received. We present results from our simulations which reveal, that depending on the spatial density of the ground station network and their signal processing quality, low-cost electronics can be used to monitor a large airspace volume by means of ADS-B TDOA without the need for elaborated and costly clock synchronization. We discuss how accurate aircraft positions and velocities can be determined and provide an outlook on the potential of this approach and its capability to monitor the integrity of obtained aircraft data for operational airspace monitoring.

@presentation{sonnleitner2023airspace, abstract = {Safe operations and efficient usage of the available airspace require precise air traffic surveillance. Classic radar systems are more and more replaced by Automatic Dependent Surveillance - Broadcast (ADS-B) which provides a higher update rate, lower operational cost and better accuracy for cooperative aircraft. Since the end of 2020 ADS-B transmitters are mandatory for a large portion of commercial aircraft in the European airspace, raising the amount of performed flights with ADS-B to 94%. As such signals are received by several ground-stations, their reception times can be used to perform multilateration in order to determine the position of the transmitter without relying on the content of the ADS-B message which can be faulty or manipulated. However, multilateration approaches require precise time synchronization among the ground stations. The synchronization of ADS-B receivers spread over a large area is complex and requires additional hardware. Therefore, we developed a passive Time Difference Of Arrival (TDOA) multilateration approach for which clocks only need to be roughly synced (e.g. using the Network Time Protocol which achieves time synchronization in the range of 10ms). In our approach the TDOA data is fed into an extended Kalman Filter which estimates relative clock offsets of all ground stations as well as positions and velocities of all aircraft from which ADS-B data were received. We present results from our simulations which reveal, that depending on the spatial density of the ground station network and their signal processing quality, low-cost electronics can be used to monitor a large airspace volume by means of ADS-B TDOA without the need for elaborated and costly clock synchronization. We discuss how accurate aircraft positions and velocities can be determined and provide an outlook on the potential of this approach and its capability to monitor the integrity of obtained aircraft data for operational airspace monitoring.}, added-at = {2024-04-29T13:47:58.000+0200}, author = {Sonnleitner, Clemens and Hobiger, Thomas}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/254a6c1748a5e2a2eb70aa3e604a17666/csonnleitner}, interhash = {e7f0adc498154fae37667c5ae93f2386}, intrahash = {54a6c1748a5e2a2eb70aa3e604a17666}, keywords = {}, timestamp = {2024-04-29T11:47:58.000+0200}, title = {Airspace Surveillance with Unsynchronized low-cost ADS-B Receivers using Time Difference of Arrival Observations}, year = 2023 }