NC URSI: National Committee of the Union radio-scientifique internationale
The International Union of Radio Science (Union Radio-Scientifique Internationale) is organized in different commissions and Switzerland is active in 6 of them: B (fields and Waves), C (Radiocommunication system and signal processing), D (Electronics and Photonics), E (Electromagnetic ENvironments and Interferences), F (Propagation) and K (Electromagnetics in Biology and Medecine).
The key event of URSI in 2017 was the General Assembly, held every third year, which is always coupled with a high level international scientific conference. The General Assembly venue was Montreal, Canada. Swiss commissions were very active, not only at the different commission meetings but also in the scientific symposium. Doctoral students had the opportunity to present their work and discuss with fellow scientists. Moreover, the Swiss E Commission organized one special session at the scientific symposium: entitled “Electromagnetic Compatibility in Wired and Wireless Systems” in which 4 papers involving researchers from France, Switzerland, Japan, Colombia and Croatia were presented. In addition, a paper dealing with the measurement of lightning parameters at the Säntis tower was presented in a special session on Lightning.
Other key events for Switzerland in 2017:
- Active participation of Switzerland through Commissions C and E on experimental campaigns on lightning. The Säntis telecommunications tower was instrumented within the framework of a research project supported by URSI, for the measurement of lightning current parameters. The site is operational since June 2010 and, as of today, more than 700 flashes have been successfully recorded by the system. The obtained data constitutes the largest dataset available to this date for upward negative flashes. During Summer 2017, a three-dimensional lightning mapping array (LMA) was deployed around the Säntis tower. LMA is a lightning location system capable of measuring the time of arrival of 60 MHz RF radiation from a lightning discharge at multiple stations, and of locating the sources of the radiation to produce a three-dimensional map of total lightning activity as a function of position and time within the cloud.
- Swiss URSI Commission B has actively participated to the organization of URSI-supported EuCAP International Conference, which was held in Paris.
- Swiss URSI Commission B fostered collaboration between the European Association on Antennas and Propagation (EurAAP) and URSI. A EurAAP corner will be published in each radio science bulletin.
The activities within Swiss URSI Commission F were related with radio propagation matters for World Radio Conference 2019 (WRC19) and ITU-R Study Group 3 (SG3: Radio Propagation). OFCOM Switzerland has submitted several contributions to ITU-R SG3 in 2017, including:
· MATLAB implementations of the following radio propagation models with validation examples were accepted by corresponding Working Parties of SG3 and published on the web page of SG3 as digital supplements to the respective Recommendations:
o ITU-R P.452-16 (Prediction procedure for the evaluation of interference between stations on the surface of the Earth at frequencies above about 0.1 GHz)
o ITU-R P.1546-5 (Method for point-to-area predictions for terrestrial services in the frequency range 30 MHz to 3 000 MHz)
o ITU-R P.1812-4 (A path-specific propagation prediction method for point-to-area terrestrial services in the VHF and UHF bands)
· In collaboration with NASA, OFCOM also updated and validated their implementation of Recommendation ITU-R P.452-16 in Excel. Both implementations (Excel and MATLAB) are important for compatibility studies in the frame of WRC19.
· In collaboration with the UK delegation to SG3, OFCOM updated the examples for validation of software implementations for Recommendation ITU-R P.2001-2 (A general purpose wide-range terrestrial propagation model in the frequency range 30 MHz to 50 GHz) and those are now publicly available on the SG3 web page as a digital supplement to Recommendation.
- Mohammad Azadifar and David Becerra (EPFL) were the recipients of URSI Young Scientist Award for their respective papers presented at the URSI General Assembly (M. Azadifar, D. Li, M. Rubinstein, F. Rachidi, "A Semi-Analytical Simplified Approach to Compute Lightning Radiated Electric Fields at Long Distances Taking into Account Ionospheric Reflection", and, D. J. Beccera, F. Vega, F. Rachidi, "Time Marching Simulation of Signal Propagation in Power Lines Loaded with Non-Linear devices").
A.K. Skrivervik, Smart wearables: an antenna challenge, 7th IEEE International Symposium on Microwave, Antenna, Propagation, and EMC Technologies, Xi'An China, 24-27 October 2017 (keynote)
A.K. Skrivervik,"Design of Wearable and Implantable Antennas", invited presentation at IWAT 2017, Athens, Greece, 1-3 March 2017
A.K. Skrivervik, M. Bosiljevac and Z. Sipus, Propagation Considerations for Implantable Antennas, 11th Conference on antenas and Porpagation, EuCAP 2017, Paris, France, pp. 1-4.
Esteban Menargues ; Mirko Favre ; Alexandros I. Dimitriadis ; Santiago Capdevila; Tomislav Debogovic ; Juan RMosig ; Maarten van der Vorst ; Emile de Rijk, Polymer-Based Metal Coated Additive Manufactured V- And W-band Antenna Feed, 11th Conference on antenas and Porpagation, EuCAP 2017, Paris, France, pp. 1-4.
M. Azadifar, F. Rachidi, M. Rubinstein, V.A. Rakov, M. Paolone, D. Pavanello, "Bipolar Lightning Flashes Observed at the Säntis Tower: Do We Need to Modify the Traditional Classification?", Journal of Geophysical Research: Atmospheres, Vol. 121, No. 14, 2016.
J. Becerra, F. Vega, and F. Rachidi, "Extrapolation of a Truncated Spectrum with Hilbert Transform for Obtaining Causal Impulse Responses", IEEE Transactions on Electromagnetic Compatibility, Vol. 59, Nr. 2, pp. 454-460, 2017.
M. Azadifar, D. Li, F. Rachidi, M. Rubinstein, G. Diendorfer, W. Schulz, H. Pichler, V. A. Rakov, M. Paolone, D. Pavanello, "Analysis of lightning-ionosphere interaction using simultaneous records of source current and 380 km distant electric field", Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 159, pp. 48-56, 2017.
M. Lagasio, A. Parodi, R. Procopio, F. Rachidi and E. Fiori, "Lightning Potential Index Performances in multi-microphysical cloud-resolving simulations of a back-building mesoscale convective system: the Genoa 2014 event", Journal of Geophysical Research: Atmospheres, doi: 10.1002/2016JD026115, 2017.
J. Beccera, F. Vega, F. Rachidi, "Time Marching Simulation of Signal Propagation in Power Lines Loaded with Non-Linear devices", 32nd URSI General Assembly, Montreal, 19-26 August 2017.
M. Azadifar, D. Li, M. Rubinstein, F. Rachidi, "A Semi-Analytical Simplified Approach to Compute Lightning Radiated Electric Fields at Long Distances Taking into Account Ionospheric Reflection", 32nd URSI General Assembly, Montreal, 19-26 August 2017.
D. Poljak, D. Cavka, F. Rachidi, "On the Use of Magnetic Current Loop Source Model in Lightning Electromagnetics", 32nd URSI General Assembly, Montreal, 19-26 August 2017.
- The 11th European Conference on Antennas and Propagation (EUCAP), Paris, France, , 19-24 March 2017.
The link with Swiss radio scientists with the international community is a key task of the URSI Commissions. This is for instance illustrated by the organization of a special session at the General Assembly by the Swiss Commission E.
Another example of international collaboration of Radio Scientists under the patronage of URSI is the international project on lightning current measurements at Säntis tower, which involves international partners from the Royal Institute of Technology and Uppsala University (Sweden), University of Florida (USA), University of Bologna (Italy), and Polytechnic University of Catalonia (Spain).
One of the main tasks of URSI is the editing of white papers on the impact of Radio Science on society in general. At the GA, the topics of the next white papers were discussed.