Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-16T07:25:50.964Z Has data issue: false hasContentIssue false

Asynchronous WAM with Irregular Pulse Repetition

Published online by Cambridge University Press:  02 August 2018

Jaroslaw Sadowski
Affiliation:
(Gdansk University of Technology, Faculty of Electronics, Telecommunications and Informatics, Department of Radio Communication Systems and Networks. Narutowicza 11/12, 80–233 Gdansk, Poland)
Jacek Stefanski*
Affiliation:
(Gdansk University of Technology, Faculty of Electronics, Telecommunications and Informatics, Department of Radio Communication Systems and Networks. Narutowicza 11/12, 80–233 Gdansk, Poland)
*

Abstract

Radiolocation systems for aviation based on Multi-Lateration (MLAT) typically use a set of synchronised ground sensors to receive radio signals broadcast by onboard transmitters. In most cases, the sensor synchronisation in Wide Area Multi-Lateration Systems (WAM) is provided by Global Navigation Satellite System (GNSS) receivers. However, in the case of synchronisation failure, there is still a possibility to estimate the coordinates of the tracked aircraft by using the measurements of the time of arrival taken by non-synchronised sensors. The article presents the principle of operation and equations for calculating the coordinates of an aircraft in an asynchronous multi-lateration system, together with the results of a computer simulation allowing comparison of the accuracy of position estimation between the asynchronous and the typical, synchronous MLAT. This paper contains also some comments on the required stability of the clock source for the sensors working in an asynchronous MLAT system.

Type
Research Article
Copyright
Copyright © The Royal Institute of Navigation 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

ICAO. (2001). Aeronautical Telecommunications Annex 10. International Civil Aviation Organization, 196.Google Scholar
Chronos Technology (2016). GPS Anomaly Event – 26 January 2016. Available online: www.chronos.co.ukGoogle Scholar
Kovach, K., Mendicki, P.J., Powers, E.D. and Renfro, B. (2016). GPS Receiver Impact from the UTC Offset (UTCO) Anomaly of 25–26 January 2016. Proceedings of the 29th International Technical Meeting of The Satellite Division of the Institute of Navigation, 28872895.Google Scholar
Langhans, W., Scheiflinger, C., Weidner, W., Auer, J., Fitzgerald, P. and Anzalone, M. (2013). Implementation of a Nationwide Wide-Area Multilateration System for Austrian Airspace. Integrated Communications, Navigation and Surveillance Conference (ICNS), 118.Google Scholar
Leonardi, M., Mathias, A. and Galati, G. (2009). Closed Form Localization Algorithms for Mode S Wide Area Multilateration. European Radar Conference, 7376.Google Scholar
Li, T. and Huang, Y.F. (2004) A Location System Using Asynchronous Distributed Sensors. Twenty-third Annual Joint Conference of the IEEE Computer and Communications Societies (INFOCOM), 620628.Google Scholar
Miyazaki, H., Koga, T., Ueda, E., Kakubari, Y. and Nihei, S. (2011). Development of High Performance WAM System. 2011 Tyrrhenian International Workshop on Digital Communications – Enhanced Surveillance of Aircraft and Vehicles, 237240.Google Scholar
Neufeldt, H. and Stanzel., S. (2013). An Operational WAM in Frankfurt Airspace, 2013 14th International Radar Symposium (IRS), 561566.Google Scholar
Neven, W.H.L., Quilter, T.J., Weedon, R. and Hogendoorn, R.A. (2005). Wide Area Multilateration. Eurocontrol Report on EATMP TRS 131/04, Version 1.1. https://www.eurocontrol.int/sites/default/files/publication/files/surveilllance-report-wide-area-multilateration-200508.pdfGoogle Scholar
Owen, M.R. (2007). Correlation of DME Pulse Trains for Use in Multilateration. Integrated Communications, Navigation and Surveillance Conference, 111.Google Scholar
Pelant, M. and Stejskal, V. (2011). Multilateration system time synchronization via overdetermination of TDOA measurements. 2011 Tyrrhenian International Workshop on Digital Communications – Enhanced Surveillance of Aircraft and Vehicles, 179183.Google Scholar
Riley, W.J. (2008). Handbook of Frequency Stability Analysis. National Institute of Standards and Technology, Special Publication 1065.Google Scholar
Sathyan, T., Humphrey, D. and Hedley, M. (2011) WASP: A System and Algorithms for Accurate Radio Localization Using Low-Cost Hardware. IEEE Transactions on Systems, Man, and Cybernetics, Part C: Applications and Reviews, 41(2), 211222.Google Scholar
Sliwczynski, L., Krehlik, P., Imlau, H., Ender, H., Schnatz, H., Piester, D. and Bauch, A. (2016). Towards sub-nanosecond synchronization of a telecom network by fiber optic distribution of UTC(k). European Frequency and Time Forum (EFTF), 14.Google Scholar
Stefanski, J. (2014). Asynchronous Wide Area Multilateration System. Aerospace Science and Technology, 36, 94102.Google Scholar
Stefanski, J. (2015). Asynchronous Time Difference of Arrival (ATDOA) Method. Pervasive and Mobile Computing, 23, 8088.Google Scholar
Tian, J., Hou, D., Xie, N. and Cheng, Y. (2017). Meter-Level TDOA Multilateration System Based On High Precision Phase Synchronization Over Fiber Optical Links. International Telemetering Conference, vol. 53.Google Scholar
Wang, Y., Leus, G. and Ma, X. (2011) Time-Based Localization for Asynchronous Wireless Sensor Networks. IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 32843287.Google Scholar
Wu, R.H. and Lefebvre, K. (2011). System and Method for Providing Timing Services and DME Aided Multilateration for Ground Surveillance. US patent no. 8063744.Google Scholar
Xiong, H., Chen, Z, An, W. and Yang, B. (2015) Robust TDOA Localization Algorithm for Asynchronous Wireless Sensor Networks. International Journal of Distributed Sensor Networks, 11(5).Google Scholar
Xu, B., Sun, G., Yu, R. and Yang, Z. (2013) High-Accuracy TDOA-Based Localization without Time Synchronization. IEEE Transactions on Parallel and Distributed Systems, 24(8), 15671576.Google Scholar
Yao, J., Lombardi, M.A., Novick, A.N., Patla, B., Sherman, J.A. and Zhang, V. (2017). The effects of the January 2016 UTC offset anomaly on GPS-controlled clocks monitored at NIST. 48th Annual Precise Time and Time Interval Systems and Applications Meeting, 155163.Google Scholar
Zhou, H., Nicholls, C., Kunz, T. and Schwartz, H. (2008). Frequency Accuracy & Stability Dependencies of Crystal Oscillators. Carleton University, Technical Report SCE-08-12.Google Scholar
Zhou, D., Wang, X., and Tian, Y. (2014) Airborne Asynchronous TDOA Based on Critical Area. IEEE International Conference on Computer and Information Technology, 715720.Google Scholar