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The DREAMS (Dust characterization, Risk assessment and Environment Analyser on the Martian Surface) experiment on Schiaparelli lander of ExoMars 2016 mission was an autonomous meteorological station designed to completely characterize the Martian atmosphere on surface, acquiring data not only on temperature, pressure, humidity, wind speed and direction, but also on solar irradiance, dust opacity and...
The Ice Cloud Imager (ICI) instrument for MetOp-SG, being developed by Airbus DS (Spain) for ESA and EUMETSAT, has successfully passed the preliminary design phase. At this stage, most of the sub-system contractors have been selected, the specifications as well as the interfaces with the satellite have been consolidated and the most critical elements are being supported by prototyping activities to...
The European Space Agency mission Soil Moisture and Ocean Salinity (SMOS) is devoted, since its launch in 2009, to provide global soil moisture and sea surface salinity values. SMOS uses an L band 2-D interferometric radiometer by aperture synthesis to obtain polarimetric brightness temperature images. This work is devoted to compute the spatial correlations in the measured antenna brightness temperature...
Self-heating affects the RF performance of power transistors and must therefore be characterized for accurate device modeling. This paper presents an active loadpull (ALP) testbed which performs continuous wave measurements with the LSNA for arbitrary loads and substrate temperatures while jointly measuring the device die temperatures with an infrared sensor. Measurements are performed for a 15 W...
We present here the latest Schottky based technology developments for the next generation of microwave, millimeter and sub-millimeter wave radiometer instruments in the framework of the joint ESA/EUMETSAT space mission — MetOp-SG. It includes the prototyping of state-of-the-art Schottky diode based mixers and multipliers and their reliability assessment for this type of long life operational space...
The ExoMars programme, which is carried out by European Space Agency (ESA) in cooperation with the Russian federal Space Agency (Roscosmos), foresees a two-steps mission to Mars. The first mission consists of an orbiter and an Entry Descent and Landing Demonstrator Module (EDM) to be launched in January 2016 and is scheduled to land on the planet during the statistical dust storm season; the second...
RFI (Radio Frequency Interference) sources, Sun signal and even land-sea transitions may generate large sidelobes that corrupt SMOS brightness temperature products and therefore, the quality of the soil moisture and sea surface salinity retrievals. This work focuses on the reduction of this Gibbs-like contamination in brightness temperature scenes using an alternative image reconstruction approach...
The organic electric insulator in polytetrafluoroethylene (PTFE) is widely used under extreme conditions of temperature and electric field. Nowadays, operating temperature of this kind of insulators can reach about 350 °C for new generations of machines, which is above than the melting temperature of the material (327 °C). These severe operating conditions can be factors of ageing acceleration and/or...
Induced mechanical deformations of organic insulator films polarized by electrical field using the Digital Image Correlation (DIC) method are presented in this work. First the validation of the technique is undertaken. Computer-generated speckle images and measurement of the coefficient of thermal expansion (CTE) for aluminum are used to evaluate the measurement accuracy of the technique. In a second...
Preliminary results obtained during the commissioning phase of the Soil Moisture and Ocean Salinity (SMOS) mission are described, devoting special attention to the characterization of the systematic errors found in the measurements and the corresponding impact in the retrieved salinity product. The identified issues and objectives to consolidate and improve the processing chain are also described.
Cuprous oxide (Cu2O) crystals were grown by the two step crystallization method in air atmosphere conditions from polycrystalline copper plates. The method comprises two stages; in the first one the copper plates are oxidized at 1020degC by some hours in line with its initial thickness. In the second stage the growth of large crystalline areas is promoted by annealing the Cu2O samples at 1100degC...
This paper presents a novel solution to the problems of clutter in the application of indoor radio-acoustic-sounding systems (RASS). A low-cost monostatic configuration comprising a horn-lens surrounded by an annular array of 40kHz acoustic transducers is constructed. A combination of the high acoustic frequency, and hence, high attenuation, and the narrow beam reduce the possibility of interference...
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