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A technique to measure the human skin emissivity in vivo is described for the frequency band 80–100 GHz. Emissivity measurements were performed on 60 participants, 35 males and 25 females, with ages ranging from 20 to 60 years. Results show that the emissivity of males is higher than that of females. The study suggests a trend in the emissivities with age and gender, which might be due to variations...
Short description of new ground radiometric complex, working on 40 GHz and 94 GHz frequencies and providing remote continuous measurements of full vertical atmosphere attenuation, effective temperature values and liquid-water content of clouds, integral content of vaporous moisture in atmosphere. The feature of the complex is the availability of digital signal processing of detected signals mode.
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...
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...
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...
A figure of merit for operating earth stations can be evaluated by G/T measurement. The performance of receiver must be retained quality for handling a weak power. Currently, the development of new S-band antenna system for THAICHOTE satellite series is being performed by GISTDA so that G/T measurement program is also required to be one of that parts. Particularly, this program attempts to be automatic...
The ongoing migration of satellite communication services to higher bands, namely the Ka- and Q-bands offer numerous advantages; however, signal propagation at these bands can be severely impaired by the various atmospheric phenomena. To assist in the validation and development of new accurate propagation models in these bands, two propagation site diversity experimental campaign have been initiated...
In this paper, long-term meteorological data are measured using six fixed surface weather stations and one radiosonde in the subtropical Arabian Gulf region, in particular United Arab Emirates (UAE). The surface refractivity profiles, Ns, and refractivity extrapolated to sea level, No, obtained from surface meteorological data using both fixed and radiosonde stations are investigated and compared...
In order to study propagation effects for future satellite communication frequencies, the Alphasat Aldo Paraboni (TDP 5) payload includes two beacon transmitters at Ka-band (19.701 GHz) and Q-band (39.402 GHz). Under ESA contract a Ground Propagation Terminal was developed to measure the co-and cross polar signals of both frequencies with the same antenna. The measurement site hosts ancillary equipment...
In recent decades, atmospheric scientists have been interested in measuring thermodynamic variables such as tropospheric water vapor and temperature with increasing temporal and spatial resolution due to their importance on the climate modeling. For this purpose, microwave radiometers have been used to measure columnar integrated water vapor. The radiative transfer equation (RTE) has been used to...
Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) is a sensor for atmospheric observation at 640 GHz from the International Space Station. Since the launch in Sep. 2009, SMILES has been showing the excellent observation performance. The results of SMILES development are summarized.
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