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In this work, the experimental implementation of a 4 × 4 stacked-patch array with linear polarization and a corporate feeding network for Ku-band is exposed. The feeding network is split into two levels, with an initial power distribution in Substrate Integrated Waveguide and a second distribution in microstrip technology. The experimental results show a matching coefficient better than −10 dB in...
A mechanically reconfigurable waveguide-slot single radiating element is presented. The tuning mechanism consists on three metallic screws introduced through the bottom wall of the feeding waveguide. The insertion length of the tuning screws and the distance to the slot are used to control the radiated signal as well as to maintain a good input matching response. Several prototypes with different...
A sensor system for simultaneous detection and monitoring of ppb concentration levels of methane and ethane using two interband cascaded lasers was developed. Long-term monitoring of these two atmospheric gases was performed in the Greater Houston area.
A sensor system based on a CW EC-QCL was demonstrated for simultaneous atmospheric HOD/H2O, N2O and CH4 detection. A 57.6m multi-pass absorption cell was employed. Wavelength modulation spectroscopy was implemented for data processing.
DNA sequence detection has a broad range of applications in different fields such as genetics, pathology, criminology, pharmacogenetics, public health, food safety, agriculture, defense and environmental monitoring. However, common DNA detection techniques present several drawbacks such as bulky size, restricted to laboratory environments, high equipment cost and time consuming experiments. Here,...
Microwave diagnostics will play an increasingly important role in burning plasma fusion energy experiments like ITER and beyond. The Collective Thomson Scattering (CTS) diagnostic to be installed at ITER is an example of such a diagnostic with great potential in present and future experiments. The ITER CTS diagnostic will inject a 1 MW 60 GHz gyrotron beam into the ITER plasma and observe the scattering...
A conformal array antenna for omnidirectional coverage in the azimuth plane at Ku band is presented. An eight-faced prism structure has been used to obtain the omnidirectional radiation pattern following a maximum theoretical ripple criterion. The radiating element consists of a rectangular waveguide ended on a cavity-slot. An equal power eight-way radial-waveguide divider has been designed to feed...
A 4 × 4 linearly-polarized stacked-patch array with a fully corporate feeding network for Ku-band is presented in its work. Antenna replication in larger arrays is straightforward with this corporate approach, which in addition prevents unintended main beam steering. The feeding structure is divided in two levels, where the first power distribution is made in Substrate Integrated Waveguide and the...
A linearly polarized 2×2 patch array fed by a corporate Substrate Integrated Waveguide network for Ku band is presented. The utilization of a corporate topology in the feeding network prevents the antenna from suffering an unintended main lobe tilt dispersion. Nevertheless, the interelement spacing increases, and so does the Side-Lobe Level. Reducing this spacing implies closer discontinuities, such...
A continuous wave, distributed feedback quantum cascade laser based absorption system was developed and demonstrated for simultaneous atmospheric CH4, N2O and H2O detection, with minimum detection limits below 2% of their typical atmospheric concentrations.
Power division/combination is a very important function for achieving high-performance power amplification in microwave and millimeter-wave systems, allowing the use of simpler individual amplifiers to provide microwave/millimeter wave high power signals. In this paper we address the development of divider/combiners in waveguide technology for large number of ports. Radial waveguide dividers will...
This paper presents an study design to assess the effectiveness of a new cognitive rehabilitation environment based on interactive video and advanced monitoring technologies.
Geosynchronous synthetic aperture radar (GEO SAR) promises novel imaging capabilities which complement low Earth orbit missions. Many configurations for GEO SAR have been studied (e.g. monostatic, bistatic, multistatic): this study considers use of Laplace plane orbits which potentially offer longer lifetimes. In the Laplace orbit plane gravitational perturbations cancel out which reduces orbit maintenance...
In this work, the fabrication and characterization of a small and portable exhaled breath sensor based on Lossy Mode Resonances (LMR) is presented. Tin oxide (SnO2) coatings fabricated onto optical fibers are used as LMR supporting coatings. The principle of operation is based on the measurement of refractive index changes by the LMR device (with an average sensitivity of 8355 nm/RIU) originated by...
Verifying the correctness of multi-processing embedded systems is a complex task and in addition to that system-on-Chips (SoC) are integrating a continuously growing number of cores. Native simulation technologies have been proposed to generate virtual platforms at the beginning of the design process, reducing porting efforts. As with any Discrete-Event simulation technique, native simulation causes...
This paper presents a comparative study of five color spaces commonly used for detecting human skin. The evaluated models were: normalized RGB, HSV, YCbCr, CIE Lab, and CIE Luv. These color spaces attempt to separate the luminance from chrominance components, which is useful to make the face skin detection illumination independent. We used the Microsoft Kinect®sensor for acquiring 705 RGB images from...
A Substrate Integrated Waveguide (SIW) has been used to feed a progressive wave linear array of 16 double stacked patches. The amplitude and phase performance has been achieved by means of coupling patches, which are placed inside the SIW. An antenna prototype has been manufactured with a multilayer PCB structure. 16 dBi and 80 % peak gain and efficiency values at 17.7 GHz have been measured. A 10%...
The filamentous bacterium Streptomyces clavuligerus (Sc), is of great commercial interest and a metabolite of interest is Clavulanic Acid (CA), a potent inhibitor of the enzyme p-lactamase that confers resistance to beta-lactam antibiotics to microorganisms both Gram positive and Gram negative. The fermentation was performed in a bioreactor 3L with a working volume of 1 L, 28 °C, 1 vvm, 500 rpm and...
The rising share of renewable energies within the generation mix has reduced the load factor of actual CCGT power plants. In this way, a more flexible operation of this technology with an increased number of annual start-up cycles is needed. Since CCGT design assumed a base load operation at nominal power with a few number of annual start cycles, plant owners have to face higher maintenance costs,...
In this paper we present a methodology to model and simulate jamming attack in Wireless Sensor Networks. The Wireless Sensor Network is described using the MARTE profile. In the UML/MARTE models Wireless Sensor Network is specified, defining the nodes that composed the network and characterizing the communication established among these nodes in the network.
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