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A heuristic algorithm based on two threshold values of a scalar indicator, given by the ratio of the brightness temperatures measured by a ground-based radiometer at 31.4 and 23.8 GHz, is employed to detect the presence, if any, of rain events along the Earth to satellite propagation path in the framework of the Alphasat Aldo Paraboni Propagation Experiment. The promising preliminary results have...
Scintillations affect the propagated signal with an unwanted aleatory oscillation at the receiver. A first analysis of data acquired from Alphasat Q-band receiver station, located in Spino d'Adda (Italy), is performed. Correlation between meteorological measurements at the ground and measured scintillation from the Q-band beacon receiver (i.e., fluctuation of the received electromagnetic field) is...
The move towards higher frequency bands like 26GHz or 32GHz for scientific satellite data downlinks calls for the need to better characterise the atmosphere at the sites where ground antennas are located. For this reason ESA is undertaking the deployment of microwave radiometers at its Deep Space station locations. This paper reports the results of the first two years of site characterisation at the...
This paper illustrates advances in dosimetry techniques for the characterization of biological entities exposed to electromagnetic fields. Specific developments for the exposure of cancer cells and tumors to pulsed electric fields are introduced. Experimental and numerical technics for the investigations of pulses with durations in the nanosecond domain (nsPEF) and intensities up of a few tens of...
Based on Vector Network Analyzer (VNA) Measurements, a model for the specular reflection behavior of printed circuit boards (PCB) in the Terahertz range has been derived. It has been calibrated to suit the behavior of the measurements using a simulated annealing algorithm. The model has been tailored for integration to ray-tracing based propagation modeling.
In satellite communications, the demand for capacity increase is met by the use of higher frequency bands, which however are severely impaired by atmospheric phenomena (rain, cloud and gaseous attenuation, scintillation). In order to study propagation effects for future satellite communication frequencies both in temperate and tropical climates, JOANNEUM RESEARCH carries out two long-term propagation...
This work aims at verifying an innovative approach for link-design optimization of deep-space missions working at Ka band. The presented approach exploits a weather forecast (WF) model coupled with a radiopropagation model to maximize data-transfer during a Ka-band downlink transmission. First, we exploit radiosounding data to tune the WF model on the geographical site of interest. As second step,...
This contribution addresses the electromagnetic feasibility of a wireless temperature monitoring inside a portion of a high-power high-frequency Cyclotron Auto-Resonance Maser (CARM) for plasma heating in the new generation of DEMO TOKAMAK machines. The scenario is investigated as potential communication channel for a UHF RFID sensor network where a cavity probe is used to both excite the coaxial...
One year statistics of water vapor density is presented. Measured data presented were obtained using meteorological sensors mounted on a mast, thus having very good height and temporal resolution. Measurement results are in the form of surface water vapor density and water vapor density gradient. Results of measurement data analysis are compared with values recommended by ITU-R.
Vanadium dioxide has recently been proven successful as a mechanism of antenna reconfigurability. We present and discuss the integration of resistive heaters underneath the surface of the vanadium dioxide thin film, on the antenna wafer. These resistive heaters are important for the implementation of a biasing mechanism that is fast (in the range of microseconds) and that does not couple electromagnetic...
Considering the imminent migration of services to the Ka- and Q-bands, a payload dedicated to propagation measurements in these bands has become available from the Alphasat satellite under the coordination of the European Space Agency. This has strongly motivated the formation of many measurement campaigns across Europe in an effort to enhance the scientific databases with new, more reliable propagation...
In this paper, the generation of passive intermodulation at standard TNC coaxial connectors is investigated. A series of tests has been performed in order to analysis the intermodulation level under different temperature circumstances. The relationship between the intermodulation response of the connectors and the change of temperature and straining on the junctions has been studied. It has been found...
In the present paper, a preliminary study for the development of a portable setup suitable for in vivo measurements of tissue dielectric properties is presented. The setup consists of a hand-held spectrum analyzer, equipped with a tracking generator to operate as a vector network analyzer, and an in-house software for the post-processing of measured parameters. The proposed setup was optimized to...
In this contribution a vectorial channel sounding system for narrowband MISO applications is presented. The channel is measured using a continuous wave signal allowing the characterization of time-variant channels and Doppler shifts within changing multipath propagation environments. The channel sounder's architecture with an analog-digital converter writing the measured data to a SD-card enables...
Clinical studies have established that adjuvant mild hyperthermia significantly increases the efficacy of radio-and chemotherapy across many tumor sites. Radiofrequency hyperthermia treatment quality is usually monitored with invasive temperature sensors, which provides limited data sampling and causes infection risks. To mitigate these issues, magnetic resonance (MR) measurements can be exploited...
Microwave thermal ablation is under consideration for minimally invasive treatment of bilateral adrenal adenomas, symptomatic of Conn's syndrome. Currently available microwave technologies are ill-suited to precise ablation of small adrenal targets. We report on our preliminary computational and experimental efforts towards the design of microwave ablation systems for targeting adrenal masses. Broadband...
An overview of ASKAP phased array feed (PAF) development is presented. New analytical and experimental techniques devised for ASKAP are described. Dedicated engineering test facilities are shown to be invaluable for system verification. Experience gained from PAF manufacture is compared with forecasts, and the importance of routine engineering demonstrated.
Temperature monitoring of tools is one key method for the prediction and detection of tool failure to prevent damage of valuable workpieces, e. g. in aircraft manufacturing. Therefore, a chipless wireless dielectric temperature sensor for machine tools, with very high temperature capability and compatibility to the harsh machine tool environment, is investigated. Based on these findings, a demonstrator...
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