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University - HAM cooperative research An effective way to address HF radio issues Dr.ir. Peter Smulders Contents • Introduction • Maxwell Stichting • HAM radio community • Examples of university – HAM cooperative research • Conclusions 2 J.C. Maxwell Stichting To promote research and education in the field of electromagnetics • Chairman: Peter Smulders, Associate Professor, TU/e • Secretary: Rob Kleihorst, EMC Lead/System designer, Philips • Treasurer: Peter Wardenier, System engineer, ASML 3 Projects and workgroups The work of the foundation is delegated by the board in the form of projects • Electromagnetic compatibility of installations on air bases, • Use of non-ionizing electromagnetic sources for health applications, • Radio experiments with the help of the Fontys-University Radiolab • High Frequency Trading over HF channels Workgroups • Workgroup MORSE manages, and performs experiments with, the Fontys-University Radiolab • Workgroup TRADIO examines High Frequency Trading over HF channels 4 Fontys-University Radiolab • Accommodated by Fontys from 2015 in Building R01 • License from Agentschap Telecom: PI5FTS • Online radio (Web Software Defined Radio) • Satellite tracking system • Weather station • Possibility of practical innovative experiments 5 HAM radio community • forms a world-wide network of licensed skilled radio operators, • allowed to use (part of) the HF band (3 – 30 MHz) for • remote sensing • narrowband (2700 Hz) but long-range communication, • enabling research towards advancements in technology for • ionospheric sounding, • emergency and disaster recovery, • low latency communications. 6 Amateur radio reporting networks • Provide real-time and archival data that could be used for • Space weather operations, forecasting and research • Potential for the study of both global and localized effects • Examples: • Reverse Beacon Network (RBN) • PSK Reporter • Weak Signal Propagation Network • HAM radio operators use MF to UHF bands to attempt two-way communications with distant locations (DXing) 7 Example of university – HAM cooperative research using amateur radio reporting networks as scientific instrument • Carried out by Virginia Tech University and a number of HAM radio operators*. • Studied the impact of an X2.9 class solar flare on HF communications • Demonstrated the merits of these networks for space weather and space science as regards both global and localized effects * N.A. Frissell et al 2014 8 Impact of an X2.9 class solar flare on HF communications * N.A. Frissell et al 2014 9 Example of university – HAM cooperative research on Near Vertical Incidence Skywave (NVIS) • NVIS uses the ionosphere to cover an area with a radius of at least 150 km around the transmitter on frequencies in the 3 – 10 MHz range. • May be used is • Areas lacking any other telecommunications infrastructure • Disaster relief communication • Must be quickly deployable 10 Example of university – HAM cooperative research on Near Vertical Incidence Skywave (NVIS) • Reseach carried out by Twente University and a number of HAM operators* to optimize performance of NVIS. • Addressed research questions • How does the NVIS propagation mechanism function and what parameters of this mechanism are important for optimization? • How can we optimize the NVIS antenna to produce the strongest signal and signal-to-noise at the receiver? • How important is the interaction between antenna and propagation mechanism? * B. Witvliet et al. 2015 11 Example of university – HAM cooperative research on High Frequency Trading over HF channels • Hibernia fiber-optical networks • Data rate: 10 Gbps • Latency: 30 ms • Cost: 1000 $/month • HF communications • Bandwidth: 2700 Hz • Latency: 20 ms • Cost: for free 12 Example of university – HAM cooperative research on High Frequency Trading over HF channels • Research is currently being carried out by Eindhoven University of Technology in cooperation with HAM radio station PI5FTP. • Research challenge: Optimize trade messages towards lowest latency and highest reliability • Research issues: • Propagation: path loss, multipath and Doppler characteristics • Transmit antenna and transmit power • Receive antenna and its location Source: VOACAP Online HF Predictions • MIMO channel characterization • Latency minimization 13 Conclusions • Amateur radio reporting networks can be valuable as scientific instruments for HF communications and remote sensing research. • Although HF communications is an old concept many technology issues are still debated and to resolve them adequately, university – HAM cooperative research can be effective. • New applications of HF communications can be envisioned which can also be interesting topics for future university-HAM research. 14 references [1] N.A. Frissell, E.S. Miller, S.R. Kaeppler, F. Ceglia, D. Pascoe, N.Sinanis, P. Smith, R. Williams, and A. Shovkoplyas, “Ionospheric Sounding Using Real-Time Amateur Radio Reporting Networks”, Space Weather, Agu Publications, American Geophysical Union, 2014, pp. 651 - 656 [2] B.A. Witvliet, E. van Maanen, G.J. Petersen, A.J. Westenberg, M.J. Bentum, C.H. Slump, and R. Schiphorst, “Near Vertical Incidence Skywave Propagation: Elevation angles and Optimum Antenna Height for Horizontal Dipole Antennas”, IEEE Antennas and Propagation Magazine, Vol. 57, No. 1, Febr. 2015, pp. 1 - 18 [3] B.A. Witvliet, “Near Vertical Incidence Skywave; Interaction of Antenna and Propagation Mechanism”, PhD thesis, ISBN: 978-90-365-3938-8, 2015 URL: http://dx.doi.org/10.3990/1.9789036539388 [4] VOACAP Online HF predictions: www.voacap.com/hf/ 15 Thank you! Any questions? 16.
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