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Design and Simulation of Microstrip Phase Array Antenna using ADSKhattak, Muhammad Kamran, Siddique, Osama, Ahmed, Waqar January 2011 (has links)
The aim of this project is to design a microstrip phase array antenna in ADS (Advance Design System) Momentum. The resonant frequency of which is 10 GHz. Two circular patches with a radius of 5.83 mm each are used in designing the array antenna. RT-DURROID 5880 is used as a substrate for this microstrip patch array design. These circular patches are excited using coaxial probe feed and transmission lines of particular lengths and widths. These transmission lines perfectly match the impedance of the circular patches. Various parameters, for example the S-parameters, two dimensional and three dimensional radiation patterns, excitation models, gain, directivity and efficiency of the designed antenna are obtained from ADS Momentum.
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Fully integrated cmos phase shifter/vco for mimo/ism applicationTavakoli Hosseinabadi, Ahmad Reza 15 May 2009 (has links)
A fully integrated CMOS 0 – 900 phase shifter in 0.18um TSMC technology is
presented. With the increasing use of wireless systems in GHz range, there is high
demand for integrated phase shifters in phased arrays and MIMO on chip systems.
Integrated phase shifters have quite a high number of integrated inductors which
consume a lot of area and introduce a huge amount of loss which make them impractical
for on chip applications. Also tuning the phase shift is another concern which seems
difficult with use of passive elements for integrated applications. This work is presents a
new method for implementing phase shifters using only active CMOS elements which
dramatically reduce the occupied area and make the tuning feasible.
Also a fully integrated millimeter-wave VCO is implemented using the same
technology. This VCO can be part of a 24 GHz frequency synthesizer for 24 GHz ISM
band transceivers. The 24 GHz ISM band is the unlicensed band and available for
commercial communication and automotive radar use, which is becoming attractive for
high bandwidth data rate.
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Anténa s řiditelným svazkem / Beam steering antennaKrejčíř, Dominik January 2021 (has links)
The master s thesis deals with the design of the beamsteering antenna. Methods of the beamsteering and the final antenna design are described. This antenna operates in the ISM band with the central frequency of 5,8 GHz. The antenna is designed in the CST Studio Suite 2020. Butler matrix was designed as a feed network implemented as substrate integrated waveguide. An array of patch antennas was used for radiation.
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Automated evaluation of three dimensional ultrasonic datasets / Évaluation automatique de données ultrasonores en 3DOsman, Ahmad 14 June 2013 (has links)
Le contrôle non destructif est devenu nécessaire pour assurer la qualité des matériaux et des composants soit en service ou à l'étape de la production. Ceci nécessite l'utilisation d'une technique d’inspection rapide, robuste et fiable. En tant que technique de contrôle principale, la technologie des ultrasons a des capacités uniques pour évaluer la position, la taille et la forme des discontinuités. Ces informations ont un rôle essentiel dans les critères d'acceptation qui sont fondés sur la sécurité et les exigences de qualité des composants fabriqués. Par conséquent, un usage intensif de la technique des ultrasons apparaît notamment dans l'inspection des composites fabriqués à grande échelle dans l'industrie aérospatiale. D'importants progrès techniques ont contribué à l'optimisation des techniques d'acquisition par ultrasons telles que la technique de "Sampling Phased Array". Cependant, les systèmes d'acquisition doivent être complétés par une procédure d'analyse automatisée de données afin d'éviter l'interprétation manuelle fastidieuse de toutes les données produites. Un tel complément permet d'accélérer le processus d'inspection et d'améliorer sa fiabilité. L'objectif de cette thèse est de proposer une chaîne d’analyse dédiée au traitement automatique des volumes échographiques 3D obtenus en utilisant la technique Sampling Phased Array. Tout d'abord, une étude détaillée du bruit de speckle affectant les données échographiques a été effectuée, puisque ce type de bruit réduit la qualité des données échographiques. Ensuite, une chaîne d’analyse complète a été développée, constituée d'une procédure de segmentation suivie d'un processus de classification. La méthodologie de segmentation proposée est adaptée aux données ultrasonores 3D et a pour objectif de détecter tous les défauts potentiels à l'intérieur du volume d'entrée 3D. La procédure de segmentation étant en priorité dédiée à la détection des défauts qui est vitale, une difficulté principale est le taux élevé de fausses alarmes qui peuvent être détectées également. La classification correcte des fausses alarmes est nécessaire afin de réduire le taux de rejet des pièces saines. Cela doit être fait sans risquer la perte des vrais défauts. Par conséquent, la segmentation doit être suivie d'un processus de classification efficace qui doit distinguer les défauts réels des fausses alarmes. Ceci a été réalisé en utilisant une approche de classification spécifique basée sur une approche de fusion de données. La chaîne complète d'analyse a été testée sur plusieurs mesures ultrasonores volumiques de composites plastiques à renfort fibre de carbone. Les résultats expérimentaux de la chaîne ont révélé une grande précision ainsi qu'une très bonne fiabilité de détection, de caractérisation et de classification des défauts avec un taux très faible de fausses alarmes. / Non-destructive testing has become necessary to ensure the quality of materials and components either in-service or at the production stage. This requires the use of a rapid, robust and reliable testing technique. As a main testing technique, the ultrasound technology has unique abilities to assess the discontinuity location, size and shape. Such information play a vital role in the acceptance criteria which are based on safety and quality requirements of manufactured components. Consequently, an extensive usage of the ultrasound technique is perceived especially in the inspection of large scale composites manufactured in the aerospace industry. Significant technical advances have contributed into optimizing the ultrasound acquisition techniques such as the sampling phased array technique. However, acquisition systems need to be complemented with an automated data analysis procedure to avoid the time consuming manual interpretation of all produced data. Such a complement would accelerate the inspection process and improve its reliability. The objective of this thesis is to propose an analysis chain dedicated to automatically process the 3D ultrasound volumes obtained using the sampling phased array technique. First, a detailed study of the speckle noise affecting the ultrasound data was conducted, as speckle reduces the quality of ultrasound data. Afterward, an analysis chain was developed, composed of a segmentation procedure followed by a classification procedure. The proposed segmentation methodology is adapted for ultrasound 3D data and has the objective to detect all potential defects inside the input volume. While the detection of defects is vital, one main difficulty is the high amount of false alarms which are detected by the segmentation procedure. The correct distinction of false alarms is necessary to reduce the rejection ratio of safe parts. This has to be done without risking missing true defects. Therefore, there is a need for a powerful classifier which can efficiently distinguish true defects from false alarms. This is achieved using a specific classification approach based on data fusion theory. The chain was tested on several ultrasound volumetric measures of Carbon Fiber Reinforced Polymers components. Experimental results of the chain revealed high accuracy, reliability in detecting, characterizing and classifying defects.
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Automated evaluation of three dimensional ultrasonic datasetsOsman, Ahmad 14 June 2013 (has links) (PDF)
Non-destructive testing has become necessary to ensure the quality of materials and components either in-service or at the production stage. This requires the use of a rapid, robust and reliable testing technique. As a main testing technique, the ultrasound technology has unique abilities to assess the discontinuity location, size and shape. Such information play a vital role in the acceptance criteria which are based on safety and quality requirements of manufactured components. Consequently, an extensive usage of the ultrasound technique is perceived especially in the inspection of large scale composites manufactured in the aerospace industry. Significant technical advances have contributed into optimizing the ultrasound acquisition techniques such as the sampling phased array technique. However, acquisition systems need to be complemented with an automated data analysis procedure to avoid the time consuming manual interpretation of all produced data. Such a complement would accelerate the inspection process and improve its reliability. The objective of this thesis is to propose an analysis chain dedicated to automatically process the 3D ultrasound volumes obtained using the sampling phased array technique. First, a detailed study of the speckle noise affecting the ultrasound data was conducted, as speckle reduces the quality of ultrasound data. Afterward, an analysis chain was developed, composed of a segmentation procedure followed by a classification procedure. The proposed segmentation methodology is adapted for ultrasound 3D data and has the objective to detect all potential defects inside the input volume. While the detection of defects is vital, one main difficulty is the high amount of false alarms which are detected by the segmentation procedure. The correct distinction of false alarms is necessary to reduce the rejection ratio of safe parts. This has to be done without risking missing true defects. Therefore, there is a need for a powerful classifier which can efficiently distinguish true defects from false alarms. This is achieved using a specific classification approach based on data fusion theory. The chain was tested on several ultrasound volumetric measures of Carbon Fiber Reinforced Polymers components. Experimental results of the chain revealed high accuracy, reliability in detecting, characterizing and classifying defects.
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