Design of dual and Wideband Rectangular Patch Antenna for C and X Band Applications

In this paper, we resolve two issues of microstrip antennas, which are miniaturization and efficiency behavior. For  that, a rectangular patch antenna with 16×18×1.6 mm3 dimensions with dual-band characteristics, was designed, fabricated and characterized.  In order to improve the problem of narrow bandwidth in  microstrip antennas, we implement in this study the slot  technique, allowing us to achieve our purpose. This technique,  lead to a good reflection coefficient and VSWR. The  characteristics of the fabricated antenna were measured and  analyzed by Vector Network Analyzer. The results show two  resonance frequencies that define two bandwidths defined by a  return loss less than -10 dB and are respectively; 7.47 GHz at a  frequency of 400 MHz, and 11.01 GHz at a frequency of 790  MHz. Also, the obtained gain has a good value and it’s very  remarkable according to the small size of the structure, with  a peak value of 6.1 dB at 12.5 GHz.  The small size and good characteristics enlarged the applications  domains of our structure, from telecommunications and  especially Radar, satellite communications to medical and  wireless applications

A New Compact Small Circular Patch Antenna for UWB Communication

A new small circular patch antenna for ultra-wideband (UWB) applications is presented. By studying this structure, it is shown that the insertion of a slot with the desired length and width in the ground plane, can lead to a large bandwidth. Our antenna, whose dimensions are 18×12×1.58 mm3, was fed by an SMA female connector with characteristic impedance of 50Ω in order to measure the return loss and VSWR and to compare them with the simulation results. The bandwidth obtained from measurements ranges from 3.52 to 13.67 GHz for VSWR < 2 and from 3.26 GHzto14.23GHz for VSWR < 3. The radiation pattern is omnidirectional on most of the operating band. High Frequency Structure Simulator (HFSS) was used for simulation whose results are in good agreement with the measured parameters

Conception et Simulation d’Antenne Rectangulaire Multicouches Pour Les Systèmes de Communication ULB

L’antenne imprimée est l’une des meilleures structures d’antenne, en raison de son coût bas et de sa conception compacte. Dans ce travail, nous présentons une antenne patch multicouches pour les applications dans les bandes X, Ku et K. En effet, nous avons étudié les performances d’une antenne patch Multicouches constituée de trois substrats de même type avec différentes tailles RT/Duroid®5880 (54x54x5.18mm3). La bande passante s’étale de 10.1GHz à 24.5GHz et présente une largeur de bande d’environ 14.4GHz (83,23%). L’analyse et la modélisation ont été effectuées en utilisant le simulateur HFSS (Ansoft High Frequency Structure Simulator) basé sur la méthode des éléments finis. Les résultats de simulation obtenus sont présentés et discutés

A new compact small circular patch antenna for UWB communication

A new small circular patch antenna for ultrawideband (UWB) applications is presented. By studying this structure, it is shown that the insertion of a slot with the desired length and width in the ground plane, can lead to a large bandwidth. Our antenna, whose dimensions are 18×12×1.58 mm3, was fed by an SMA female connector with characteristic impedance of 50Ω in order to measure the return loss and VSWR and to compare them with the simulation results. The bandwidth obtained from measurements ranges from 3.52 to 13.67 GHz for VSWR < 2 and from 3.26 GHzto14.23GHz for VSWR < 3. The radiation pattern is omnidirectional on most of the operating band. High Frequency Structure Simulator (HFSS) was used for simulation whose results are in good agreement with the measured parameters

A miniaturized printed UWB antenna with dual notching for X-b and and aeronautical radio navigation applications

A low cost miniaturized UWB microstrip antenna with dual notched band for X band and aeronautical radio navigation (ARN) is presented in this article. The antenna (19 16×"&gt; 25 mm2) is composed of a half-circular ring as a radiation patch with an incomplete ground plane. The measured results indicate a fractional bandwidth of 112% for 16S11≤-"&gt; 10 dB between 3 to 10.6 GHz. The dual notched band has been achieved by incorporating window shaped microstrip closed ring resonators at the rear surface of the designed structure. The first notch band is centered at 7.5 GHz (7 8.1 GHz) to reject interference with X-band downlink (7.25 to 7.74 GHz) and second band centered at 9.1 GHz (8.6 9.4 GHz) to reject interference with aeronautical radio navigation (ARN) (8.7 to 9.2 GHz). The simulated and measured return loss, radiation pattern, and gain shows good agreement which confirms the applicability of the designed antenna for the intended UWB applications

Comportement et cinétique de transformation martensitique sous sollicitation multiaxiale des matériaux métastables

Phase transformation considerably influences the thermomechanical properties of metastable materials. This is reflected in the numerical model that simulates the behavior of these materials for the calculation codes and require experiments.Thus, the present work concerns the characterization of the axial and multi-axial behavior of two iTRIP steels, 301L steel and 304L steel in addition to a shape memory alloy based on CuAlBe. This characterization is coupled with monitoring of phase transformation kinetics through the measurement of the electrical resistance.The first chapter is a bibliographic study of the two classes of metastable materials mentioned above as well as the phase transformation phenomenon and its characterization techniques. The second chapter deals with uniaxial thermomechanical tests on a steel iTRIP to validate the phase assay. The multiaxial thermomechanical testing performed on specimens tubular steel 304L iTrip will be presented.The third chapter is devoted to uniaxial tests performed on CuAlBe spicemens and realization phase doping in a three-phase case. Also, the validation of the assumption of linearity between the martensite volume fraction and the equivalent transformation strain in the case of proportional and non-proportional loading is done.La transformation de phase influence considérablement les propriétés thermomécaniques des matériaux métastables. Elle est prise en considération dans des modèles numériques qui simule le comportement de ces derniers dans des codes de calcul et qui nécessitent des résultats expérimentaux. Ainsi, ces travaux concernent la caractérisation du comportement axial et multiaxial de deux aciers iTRIP à savoir l’acier 301L et l’acier 304L ainsi qu’un alliage à mémoire de forme à base de CuAlBe. Cette caractérisation est couplée avec un suivi de la cinétique des transformation de phase entreprise par la mesure de la résistance électrique. Le premier chapitre est une étude bibliographique des deux classes de matériaux métastables cités précédemment ainsi que du phénomène de transformation de phase et les techniques permettant sa caractérisation. Le deuxième chapitre, s’intéresse aux essais uniaxiaux thermomécaniques réalisés sur un acier iTRIP afin de valider la méthode de dosage de phase. Aussi, les essais thermomécaniques multiaxiaux réalisés sur des éprouvettes tubulaires en acier iTRIP 304L y seront présentés. Le troisième chapitre est consacré aux essais uniaxiaux réalisés sur des éprouvettes de CuAlBe ainsi qu’au dosage de phase des cas biphasé et triphasé. Aussi, la validation de l’hypothèse de linéarité entre la fraction volumique de martensite et la déformation de transformation équivalente dans le cas de chargements multiaxiaux proportionnels et non proportionnels est faite

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La transformation de phase influence considérablement les propriétés thermomécaniques des matériaux métastables. Elle est prise en considération dans des modèles numériques qui simule le comportement de ces derniers dans des codes de calcul et qui nécessitent des résultats expérimentaux. Ainsi, ces travaux concernent la caractérisation du comportement axial et multiaxial de deux aciers iTRIP à savoir l’acier 301L et l’acier 304L ainsi qu’un alliage à mémoire de forme à base de CuAlBe. Cette caractérisation est couplée avec un suivi de la cinétique des transformation de phase entreprise par la mesure de la résistance électrique. Le premier chapitre est une étude bibliographique des deux classes de matériaux métastables cités précédemment ainsi que du phénomène de transformation de phase et les techniques permettant sa caractérisation. Le deuxième chapitre, s’intéresse aux essais uniaxiaux thermomécaniques réalisés sur un acier iTRIP afin de valider la méthode de dosage de phase. Aussi, les essais thermomécaniques multiaxiaux réalisés sur des éprouvettes tubulaires en acier iTRIP 304L y seront présentés. Le troisième chapitre est consacré aux essais uniaxiaux réalisés sur des éprouvettes de CuAlBe ainsi qu’au dosage de phase des cas biphasé et triphasé. Aussi, la validation de l’hypothèse de linéarité entre la fraction volumique de martensite et la déformation de transformation équivalente dans le cas de chargements multiaxiaux proportionnels et non proportionnels est faite.Phase transformation considerably influences the thermomechanical properties of metastable materials. This is reflected in the numerical model that simulates the behavior of these materials for the calculation codes and require experiments.Thus, the present work concerns the characterization of the axial and multi-axial behavior of two iTRIP steels, 301L steel and 304L steel in addition to a shape memory alloy based on CuAlBe. This characterization is coupled with monitoring of phase transformation kinetics through the measurement of the electrical resistance.The first chapter is a bibliographic study of the two classes of metastable materials mentioned above as well as the phase transformation phenomenon and its characterization techniques. The second chapter deals with uniaxial thermomechanical tests on a steel iTRIP to validate the phase assay. The multiaxial thermomechanical testing performed on specimens tubular steel 304L iTrip will be presented.The third chapter is devoted to uniaxial tests performed on CuAlBe spicemens and realization phase doping in a three-phase case. Also, the validation of the assumption of linearity between the martensite volume fraction and the equivalent transformation strain in the case of proportional and non-proportional loading is done

Design of H-slot Patch Antenna for Ultra Wideband

The printed antenna is one of the best antenna structures, due to its low cost and compact design. In this paper, we studied a new approach to improve the effectiveness of radiation and performance antennas with the miniaturization of its size. Indeed, we propose a miniature rectangular printed antenna with three slots in the form of H and which satisfies the multilayer UWB characteristics in terms of bandwidth and reflection coefficient. This antenna is for a system for detecting malignancy the microwave imaging. We use some techniques of miniaturization and expansion of bandwidth in order to achieve our goal. The study was made for the band of UWB frequency range from 3GHz to 10GH