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Abstract-In the framework of the ITALSAT campaign various European institutions carried out propagation measurements at V band. In this frequency band, signal reception in a satellite-to- Earth or Earth-to-satellite path may suffer severely from signal attenuation due to meteorological effects such as rain, snow, hail, fog, clouds, etc., where rain provides the most significant contribution. In this paper, a joint analysis of the ITALSAT propagation measurement campaigns at 39.6 GHz (precisely 39.592 GHz) carried out at both Oberpfaffenhofen, close to Munich, Germany, and Spino d'Adda, close to Milan, Italy, is presented. For both stations long-term attenuation statistics are available and reveal that signal attenuation due to meteorological effects depends very much on the season and on the time of the day. Signal attenuation can be compensated by an appropriate fade margin. In this paper, we show that the required fade margin to guarantee a target link availability has to be chosen very carefully, since it depends very much on the time interval upon which availability is defined. We consider complete years, ITU-R recommendations, all single months of the year, worst months, and spring, summer, fall, and winter. Furthermore, we evaluate diurnal variations for four time intervals: 00:00-06:00, 06:00-12:00, 12:00-18:00, and 18:00-24:00. [ABSTRACT FROM AUTHOR]

As a consequence of electric power systems growth and further interconnection, the fault current levels increase. Therefore there is the interest in devices which are able to limit fault currents. The Superconducting Fault Current Limiter (SFCL) is an innovative device able to limit the short-circuit currents to lower levels, so that no component or underrated switching equipment in the system becomes overloaded but can be operated safety. In this work, we report on design and development of a 9 kV/15 MVA-class SFCL for MV distribution system, based on 1G and 2G HTS. The project final goal is to develop a SFCL for a MV distribution system, including design, fabrication, test at a high power test facility, installation and operation in the Milan area distribution network. AC losses for different HTS winding arrangements and SFCL short-circuit simulation results for two selected network case studies are reported and discussed. [ABSTRACT FROM AUTHOR]

A model is presented that extends the applicability of the propagation data collected during a long measurements campaign in a particular site and for a particular radiolink, to a generic link in a generic site. In fact, the objective of the model is to create a set of attenuation time series to be used in the design of advanced TLC systems. The model assumes that the marked differences of the rain statistics observed in various locations are, in first approximation, mainly due to the different frequency of occurrence of the various rainy events rather than to their shape. Starting from this assumption the model selects, from a large database of rain attenuation events collected in a particular site, a subset that, after an appropriate frequency and elevation scaling, can be used to represent time series of attenuation recorded in other experimental conditions (as for both site and link). The model has been applied to the attenuation data collected at Spino d'Adda (Milan, Italy) during the ITALSAT propagation campaign in order to simulate attenuation time series in several different links and sites. The model demonstrated good performance both in link conditions and climates, similar and different from the Spino d'Adda ones. [ABSTRACT FROM AUTHOR]