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Special Session: Full-duplex communications for 5G & Beyond and IoT applications; International audience; In this paper, a wideband dual-polarized full-duplex antenna array is presented. The array is formed of four dual-polarized Vivaldi antennas with a modified feeding to obtain total symmetry between the orthogonal polarizations. The array is fed by a wideband 4-way balun that can split the input signal into four output signals of equal amplitudes with two of them being phase inverted with respect to the other two. The simulated results indicate that the array is matched from 2 GHz to beyond 20 GHz with an average gain of 11 dBi. Also, under ideal conditions, the array can achieve a high level of self-interference cancellation (≥120 dB), and this level is estimated to be better than 40 dB in practice.

International audience; This paper demonstrates a single topology to implement ultra-wideband in-phase and 180° out-of-phase power dividers which will be dedicated for ultra-wideband frontends and balanced antenna systems that require a decent amount of isolation between ports. Both power dividers are formed of two couples of microstrip-to-slotline transitions terminated with radial stubs and then cascaded with a multisection Wilkinson power divider. A parametric study of the microstrip-to-slotline transition is performed to identify the main parameters' influence on its frequency response, followed by a full-wave optimization. Both power dividers are designed on RO4003C substrates and both have the same size of × mm 2. Simulation results show that the power dividers can operate between 4 and 40 GHz with less than 6 dB insertion loss and with small amplitude and phase imbalances between output ports. And most importantly, both devices have at least 20 dB of isolation between output ports over the entire bandwidth. Keywords-in-phase power divider, out-of-phase power divider, balun, multisection Wilkinson power divider, microstrip-to-slotline transition, ultra-wideband.

This paper demonstrates a single topology to implement ultra-wideband in-phase and 180° out-of-phase power dividers which will be dedicated for ultra-wideband frontends and balanced antenna systems that require a decent amount of isolation between ports. Both power dividers are formed of two couples of microstrip-to-slotline transitions terminated with radial stubs and then cascaded with a multisection Wilkinson power divider. A parametric study of the microstrip-to-slotline transition is performed to identify the main parameters’ influence on its frequency response, followed by a full-wave optimization. Both power dividers are designed on RO4003C substrates and both have the same size of $22 \times 38 mm^{2}$. Simulation results show that the power dividers can operate between 4 and 40 GHz with less than 6 dB insertion loss and with small amplitude and phase imbalances between output ports. And most importantly, both devices have at least 20 dB of isolation between output ports over the entire bandwidth.

International audience; Decreasing the electric length of an antenna results in increasing its input reactance that becomes greater than its input resistance, resulting in a significant rise in its quality factor and in a drastic reduction of its potential operating bandwidth. For such small antennas, namely ESA for Electrically Small Antenna, passive matching is restricted by the gain-bandwidth theory, providing narrow bandwidths and/or poor gain. This limitation can be overtaken by using antenna matching networks based on non-Foster components. In previous studies, non-Foster components are used to cancel the reactance part of the ESA, and then passive matching may be introduced to transform the net input impedance toward 50Ω, which leads to an increase in the bandwidth. In this paper, a design methodology is put forward on three different topologies all based on combined passive and active matching networks. A described step-by-step design to decrease the antenna quality factor is discussed. A comparison is made between these topologies along with a discussion on their limitations and ability to increase the bandwidth and radiation efficiency of ESA. The third topology presented in this paper is a novel one that proposes a three-stage matching network and exhibits both the widest matched bandwidth and an increase in the efficiency of the whole system compared to previous approaches. In order to make this comparison, a new indicator to estimate the whole system radiated power efficiency is introduced and validated by comparison with a full EM simulation. Moreover, actual implementation of the two most interesting techniques are detailed and associated measured results are carefully compared to simulations.

International audience; This paper describes the synthesis method and implementation in 65-nm CMOS technology of a compact analog phase-shifter (PS) dedicated to 24/28 GHz applications. This PS delivers a phase shift continuously tunable from 0 to 55° and is particularly suited for on-chip or in-package phased-array antenna. The proposed topology, which is based on an all-pass circuit that includes coupled microstrip lines and varactors as tunable components is intrinsically compact and shows an interesting phase-range vs capacitance-variation ratio.

International audience; A novel tunable channelized two-branches passive bandstop filter using a reconfigurable parallel-coupled-line-based Phase Shifter (PS) is presented. The filter topology uses the signal destructive principle and aims to protect the receiver against an unwanted interference signal received by the antenna. The global filter topology contains two branches, each of which has a different function. The bandpass tunable branch selects the frequency to be rejected while the reconfigurable PS plays the signal invertor role. The simultaneous tunability of both bandpass and PS branches is ensured by using identical varactor diodes and features 550-700 MHz tuning range. In addition of having a constant and relatively high rejection level over all the tuning range and low insertion loss in the passband area, the filter guaranties ultra-low power consumption. Moreover, synthesis equations are proposed and used to illustrate the operating principle, and finally validated by comparing simulations results to measurements.

International audience; In this paper, an active phase shifter that features a frequency independent transmission phase response over a wideband frequency ranging from 2 GHz to 4 GHz is designed based on Non-Foster elements. The main objective of this study is to get a phase in transmission slightly tunable around 180° while having low insertion loss and minimum return loss in the considered band. The active phase shifter (PS) topology requires negative capacitances that are obtained by using Negative Impedance Converter (NIC) circuits, which convert load impedance into a negative impedance. However, it is shown that the actual realization of NIC from cross-coupled pair (XCP) with FETs leads to undesired parasitic resistance that has a significant effect on the performance of the phase shifter. Therefore, the negative capacitance used in the PS are built up by cascading two different topologies of XCP circuit that compensates the residual resistance of each other. Moreover, one of the XCP topology is also internally modified to decrease furthermore this resistive part at the implementation level.

International audience; In this paper a BAVA (Balanced Antipodal Vivaldi Antenna) antenna is designed and optimized to be used in direct breast contact to operate in the 3.1-10.6 GHz band. A bi-static study in the time domain is proposed to investigate the presence of the tumor. The tumor was first inserted in the fat tissues at 4 mm from the skin and then inserted deeper at 2 cm in the glandular tissues to validate the used approach. Finally a microwave breast image was constructed based on the recovered time domain signals for both cases.

International audience; This work introduces a new design approach of multilayer Electromagnetic Band Gaps (EBGs) for wideband antenna isolation in a Full-Duplex transceiver. The design methodology is applied to a conventional type of EBGs in order to improve its initial performance in terms of bandwidth and size. By stacking multiple dielectric layers with integrated vias, an enhancement of the relative bandwidth of the band gap and a strong miniaturization of the unit cell is achieved. The dispersion diagrams of the proposed EBGs are studied and full-wave electromagnetic simulations are realized to validate the isolation level and the proposed lumped model of the final structures.

International audience; This work presents a new design approach of wideband multilayer Electromagnetic Band Gaps (EBGs) suitable for both on package antenna isolation and switching noise suppression in high speed digital circuits. Depending on thetarget applications, the design principle is implemented from two conventional types of EBGs in order to improve their initial performance. By stacking multiple dielectric layers with integrated vias in both types of EBGs, it’s possible to achieve dual band performance, to enhance the relative bandwidth of the first band gap and to miniaturize the unit cell. The dispersion diagrams of the multilayer EBGs are proposed and full-wave simulations are performed to validate the antenna isolation and noise suppression bandwidths of the final structures.

International audience; In this paper, the design and test of different microwave antennas and sensors for breast cancer detection are presented. The sensors are designed and optimized to be used in direct skin contact, and for this purpose a specific breast phantom model is proposed. First, a miniaturized microstrip back-cavity Hilbert fractal antenna, operating in the ISM band (2.4–2.5 GHz), was designed. Then, this antenna was used to investigate the possibility of detecting the presence of breast tumors based on a narrowband frequency method that monitors the shift of the antenna frequency response. The antenna prototype was fabricated and tested in real in vivo measurement conditions on two different patients diagnosed with breast cancer. Measurement results have led after a comparison with the retro-simulation results of the structure to a more realistic breast model and to draw the limitations of this narrowband frequency method. As a time domain study seems to be more relevant, an UWB monopole antenna of dimensions 3 cm × 3 cm, to be used in direct contact with the breast model was designed. This antenna was optimized to both enhance the antenna/human body matching and to maximize the transfer of energy into the breast phantom by using a cavity, increasing by this way the detection potential. In order to improve the sensor’s directivity and enhance the electromagnetic field level inside the breast, a balanced antipodal Vivaldi antenna was also designed and optimized for a direct breast contact to operate in the 3.1–10.6 GHz band. A mono static and a bi static study in the time domain are finally proposed to investigate the presence of the tumor.

A wideband switched beam antenna array system operating from 2 to 5 GHz is presented. It is comprised of a $4\times 1$ Vivaldi antenna elements and a $4\times 4$ Butler matrix beamformer driven by a digitally controlled double-pole four-throw RF switch. The Butler matrix is implemented on a multilayer structure, using 90° hybrid couplers and 45° phase shifters. For the design of the coupler and phase shifter, we propose a unified methodology applied, but not limited, to elliptically shaped geometries. The multilayer realization enables us to avoid microstrip crossing and supports wideband operation of the beamforming network. To realize the Butler matrix, we introduce a step-by-step and stage-by-stage design methodology that enables accurate balance of the output weights at the antenna ports to achieve a stable beamforming performance. In this paper, we use a Vivaldi antenna element in a linear four-element array, since such element supports wideband and wide-scan angle operation. A soft condition in the form of corrugations is implemented around the periphery of the array, in order to reduce the edge effects. This technique improved the gain, the sidelobes, and helped to obtain back radiation suppression. Finally, impedance loading was also utilized in the two edge elements of the array to improve the active impedance. The proposed system of the Butler matrix in conjunction with the constructed array can be utilized as a common RF front end in a wideband air interface for a small cell 5G application and beyond as it is capable to simultaneously cover all the commercial bands from 2 to 5 GHz.

International audience; An hybrid architecture of a compact, low-cost and gain compensated delay line switchable from 1 m to 250 m is presented in this paper. The delay line takes place in a Radar Target Simulator to allow testing automotive radar sensors. A hybridization of different technologies is presented to simulate delays on the entire range with a 20 cm resolution step and a frequency band of 800 MHz. Three technologies, LTCC components, optical fibers and SAW filters, were combined to cover the entire distance range. The whole system also ensures a gain compensation and equalization in the entire frequency band, as well as the simulation of the Radar Cross Section (RCS) of various targets over the entire distance range.

This article describes a synthesis method dedicated to the design of frequency-independent phase shifters (PSs). This innovative PS structure consists in a transmission line cascaded with a negative group delay (NGD) active circuit so that the absolute constant group delays generated by both of them are identical but of opposite signs. So, in principle, it exhibits a constant overall phase and a group delay close to zero. Broadband linear positive phase slopes are obtained through use of an NGD active circuit whose characteristics are recalled prior to the extraction of the PS synthesis relations. The design and simulations of a PS of compact size are reported. The experimental results confirm the expected frequency-independent transmission-phase value of 145° ± 10° with an insertion gain of 2 ± 2 dB over a 160% relative frequency band. At last, future prospects allowed by the specific properties of this PS are presented. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2010. © 2011 Wiley Periodicals, Inc.

International audience; In this paper, three methods to reject the first spurious harmonic in parallel-coupled microstrip filters are investigated. The authors proposed an extension of these approaches to also suppress the second unwanted passbands while keeping the initial passband practically unchanged. Then, two of these techniques are combined to achieve a wider upper stopband. Indeed, the sinusoidal perturbation technique is well combined with overcoupled end sections to reject the first three spurious passbands of an order three filter. A comparison of simulations and experimental results is made, with a discussion on each method efficiency and possible applications to higher order filters.

In this paper, an analog phase shifter is designed by using a novel all-pass topology. The phase shift can be continuously adjusted from 0 up to 380° by biasing varactor-diodes while maintaining the differential phase shift constant across the 6.7 GHz - 7.7 GHz band. This two-stage circuit is simple and compact with respectively insertion losses of 2.9 dB +- 1.3 dB, return losses better than 9.4 dB and a differential phase shift flatness of +- 11° in the worst case. With a 90.5°/dB Figure-of-Merit, this topology presents an interesting trade-off between low-cost, low loss, large phase-shift range, phase flatness and bandwidth. Measurements are discussed and carefully compared to current competing topologies.

International audience; This paper deals with the experimental validation of equalization technique of RC-line degradations based on a negative group delay (NGD) active circuit. The feasibility of this method is illustrated by brief theoretical recalls. Formulas permitting the synthesis of this NGD circuit according to the RC-line parameters are proposed. Then, the analytical predictions are verified by experimental results, which also provide evidence the efficacy of the technique for prototypes in planar hybrid technology. So, for an input square-wave pulse of 25 Msym/s-rate, the rise-time and the propagation delay of the regarded RC-circuit were respectively reduced by 71.4% and 86.4%. As expected, the recovered measured signal shows enhancement of both the raising and trailing edges. Finally, the main benefits provided by this technique compared to the use of repeater are discussed.

8th International Conference Interconnection Technology of Electronic Board May 21-22-23, 2008 Brest; Nowadays, because of the continuous technological progress in the very deep-submicron area, the overall circuit performance is dominated by interconnect delay. So, the interconnect line propagation delay can no longer be neglected. The most popular among the theoretical models available in the literature to assess the effects of these lines has been proposed by Elmore in 1948. We recently developed an active circuit able to produce negative group delay (NGD) and gain at first in the microwave domain, and secondly dedicated to base band signals. Thanks to this new concept, we proposed an innovative technique to reduce interconnect effects.

Sometimes electromagnetic approach can not be directly used to design microwave circuits. So, finding new techniques based on circuit theory is still of interest to analyse and design microwave systems. To keep the accuracy of these techniques as far as possible while increasing frequency, a minimisation of several spurious effects must be done. These effects may be brought by discontinuities. That's why, nonuniform transmission lines can be used to avoid discontinuity effects, particularly in microwave filters. An original approach to analyse and optimise Continuously Varying Transmission Lines (CVTL) is used to design planar microwave filters. The method is based on exact solutions of the telegrapher's relations of non-uniform transmission lines. The CVTL scattering parameters are investigated in detail in the frequency domain. In order to validate the method, several different CVTL are built using microstrip and coplanar waveguide technology. Measured data are presented and compared with theory over a wide frequency range. Then, the technique based on CVTL is used to accurately analyse arbitrary coupled nonuniform transmission lines. This approach sounds interesting to design band-pass filters. For several examples, measurements are compared to simulation results. By comparison to usual techniques our method brings additional degrees of freedom. They are used to control the out-of-band responses of coupled band-pass filter. Handling capability and method accuracy are validated by comparing simulation and experimental results., La modélisation numérique des équations de Maxwell n'étant pas facilement utilisable pour la conception de tous les circuits hyperfréquences, il apparaît important de développer en parallèle des méthodes d'analyse et de synthèse de dispositifs micro-ondes fondées sur la théorie des circuits. Pour conserver ce type d'approche, une minimisation des différents problèmes parasites doit être respectée. En effet, l'un des problèmes inhérents aux réseaux à lignes de transmission est la modélisation des discontinuités entre les différentes largeurs de ligne. Ce problème devient important dans la conception de filtres planaires. Nous définissons une structure initiale exempte de tels sauts d'impédance, ce qui permet de conserver, par rapport à des structures classiques, une configuration optimale à des fréquences supérieures. La 1ère partie théorique décrit la méthode originale construite à partir d'outils mathématiques simples et “ portables ”, pour l'analyse de lignes de transmission à variation continue d'impédance. Dans la 2ème partie, consacrée à la réalisation de filtres passe-bas et coupe bande, les avantages de la méthode sont mis en avant. Le réseau à variation continue d'impédance présente, de part sa structure même, un nombre supérieur de degrés de liberté par rapport aux réseaux classiques. Ce principe est mis en application pour générer des filtres passe-bas à bandes atténuées élargies. La souplesse et la précision de la méthode en font un outil intéressant pour la réalisation de filtres passe-bande à partir de lignes couplées en technologie microruban. Dans la dernière partie, l'approche est d'abord utilisée pour compenser la dégradation de la réponse du filtre, due à la configuration microruban. Les degrés de liberté de la méthode utilisée étape par étape permettent ensuite la conception de filtres passe-bande complexes avec de larges bandes de réjection.

Cet article presente une maquette pedagogique simple et bon marche (estimee a une trentaine d’euros) destinee a l’enseignement de l’electronique analogique. Elle permet en particulier d’etudier des fonctions de base telles que les oscillateurs et les generateurs de fonctions sur une seance de trois heures. Cette manipulation a ete realisee dans le cadre de l’enseignement des travaux pratiques du module EN3 « Fonctions associees au traitement et a la transmission de l’information » [1] du programme de la filiere Genie Electrique et Informatique Industrielle des IUT. Elle vient en complement des cours et des travaux diriges. Cette unite d’enseignement est suivie par tous les etudiants de 2eme annee du departement GEII de l’IUT de Brest. Face a l’avenement du tout numerique dans les programmes d’enseignement actuels, il semble important pour nous electroniciens, de sensibiliser les etudiants a la mesure de signaux analogiques et a la comprehension de phenomenes physiques sur des composants electroniques elementaires etudies en 1ere annee. Les futurs techniciens mettent en pratique des notions theoriques telles que le demarrage d’un oscillateur, le role d’un amplificateur, le role d’un reseau de reaction ou l’interet d’une contre-reaction. Ils peuvent aussi evaluer les limitations dues aux composants, discuter de la qualite d’un signal, observer des distorsions et proposer des solutions pour ameliorer ce signal. Les calculs preparatoires et les resultats de mesure seront ensuite verifies par la simulation a l’aide du logiciel professionnel @Altium Designer [2] utilise dans notre departement. Les etudiants d’IUT sont demandeurs car ils apprecient le cote concret de la manipulation qui leur permet de mieux comprendre les notions theoriques vues en cours et en travaux diriges. De plus, ils ont ete eux memes acteurs de ce travail car cette maquette didactique est le fruit de projets tutores menes par les etudiants de 1ere annee. L’evaluation de cet enseignement comporte deux parties : un compte-rendu classique par binome que les etudiants nous remettent a la fin de la seance et un petit controle ecrit d’un quart d’heure sur table, sans document, en fin de seance.

National audience; Cet article propose une technique pour le contrôle de la dispersion et du temps de propagation de groupe (TPG) dans le domaine microonde à partir de lignes de transmission non-uniformes. Une ligne microruban périodique dont le profil suit une variation continue est synthétisée pour l'obtention d'une variation linéaire de TPG en fonction de la fréquence d'environ -0,25ns/GHz de 3,1 à 10,6 GHz. Cette ligne qui fonctionne en réflexion est initialement générée par des équations analytiques, puis simulée et optimisée grâce à un modèle hiérarchique de lignes non-uniformes dont le profil est défini par interpolation cubique.

International audience; Mott transition materials seem particularly promising to design reconfigurable devices. In this paper, Vanadium Dioxide (VO2) is studied and characterized to design switches and elementary RF devices. The study shows experimentally promising RF performances under electrical control and also for an optical excitation of the VO2 with ultra-short switching time. These results put forward the use of VO2 switches as a core function to design ultra-fast purpose RF devices dedicated to future military and civilian standards.

National audience; A small-size and low-cost wideband delay line tunable over a 1250:1 delay range is presented in this paper. The delay line should take place afterward in an automotive radar target simulator. The initial specifications require merging different technologies to simulate the desired distances from 0.2 m to 250 m with a high resolution and a large frequency band better than 800 MHz. Three technologies are highlighted, SAW filters, optical fibers and LTCC components, to generate delays between 1.33 ns and 1.67 µs. Prototypes were realized, tested and characterized for each technology. Moreover, a hybridization of these technologies is proposed together, with the whole delay line simulations.

This chapter is available on the following open access link: http://www.intechopen.com/books/microwave-and-millimeter-wave-technologies-modern-uwb-antennas-and-equipment/study-and-application-of-microwave-active-circuits-with-negative-group-delay; A simple topology of an NGD active circuit consisting of a FET terminated by a shunt RLC-resonant network and dedicated to the microwave signals was proposed and extensively studied. To our knowledge, in this chapter, the first experimental time-domain demonstration of a circuit able to exhibit simultaneously gain and NGD in microwave domain is proposed. By injecting in the NGD circuit a sufficiently smoothed input short-pulse modulating a sine carrier, one gets an output having an envelop peak in advance compared with the input one. Of course, this phenomenon does not contradict the causality principle. It is also worth emphasizing that the tested circuit respects all required criteria of classical active microwave devices such as gain, matching and stability. As predicted in theory (Ravelo et al., 2007a, 2007b, 2007c and 2008a), for a prototype implemented in planar technology, we have measured in time-domain a pulse peak advance of about -2 ns or 24% of the 1/e-input pulse half-width without attenuation. It is also interesting to note that through this experimentation, the input noise contribution did not destroy the occurrence of time-domain advance induced by the NGD active circuit. Moreover, in this chapter, thanks to the S21-magnitude form, the understudied NGD circuit is able to exhibit a pulse compression phenomenon with a possibility of amplification. Then, it should be worth using the presented NGD active topology to compensate for dispersion effects and especially to reduce the intersymbol interference in certain telecommunication channels. As a potential application of this NGD circuit, a new principle of frequency independent phase shifter is proposed. By cascading a classical transmission line with this NGD circuit, a constant phase value is obtained. The efficiency of this principle was demonstrated by measurement. Indeed, a constant phase value of 90°±5° was obtained within a 76% relative frequency band centred at about 1.5 GHz. The impacts of the PS parameter variations and sensitivity analysis are stated. The main benefits of this NGD active PS concerns its compactness and also the facility to generate very low group delay, and the broad band characteristics. Besides, a two-stage NGD PS was also designed; the simulation results showed a bandwidth enhancement of the constant phase up to 125%. Some fields of applications such as the design of broadband active balun for RF front end architectures are discussed. As ongoing research, design of reconfigurable devices dedicated to telecommunication applications is envisaged. Future investigations will be devoted to the design of NGD devices able to operate at higher frequencies through the use of distributed elements. In this optic, the implementation of MMIC devices based on distributed elements is envisaged.

National audience; Un nouveau type de déphaseur analogique à variation continue de phase est présenté. Il est basé sur l'association du déphaseur de Schiffman et de varicaps assurant l'agilité en phase. Cette topologie assure un nouveau compromis particulièrement intéressant en terme de bande passante, de plage de variation de phase, de pertes d'insertion, de compacité et de coût. L'application principale visée est le réseau d'antennes à balayage. Un prototype à une seule cellule a été conçue sur la bande 4-7 GHz. La validation expérimentale montre un très bon accord avec la simulation avec une agilité en phase de plus de 180° et permet d'envisager les 360° avec seulement deux cellules, tout en assurant un niveau de pertes d'insertion très raisonnable pour un déphaseur analogique.

National audience; Dans cet article, une nouvelle topologie de déphaseur analogique variable est proposée. Elle est obtenue en inter-combinant un déphaseur de Schiffman et un déphaseur passe-tout mixte distribué/localisé. Ce déphaseur compact présente l'avantage d'une forte agilité en phase pour une variation limitée de la capacité de la varicap. Les mesures du dispositif réalisé en technologie hybride microruban confirme une variation continue du déphasage jusqu'à 180° pour un circuit à une seule cellule. Sur l'ensemble de la bande considérée, i.e. 4-7 GHz, les pertes d'insertion sont à 1,8 dB+- 1 dB. Cette topologie présente un compromis entre plage de variation, compacité, pertes, platitude de phase particulièrement intéressant.

© 2010 EuMA; International audience; This paper describes an active phase shifter, which exhibits a frequency-independent phase shift over the ultrawideband (UWB) frequency range. The design of this pure phase shifter relies on the use of a negative group delay (NGD) circuit. The topology of the active NGD cell is based on a Field Effect Transistor in cascade with a series resonant network. A 90°±5° phase shifter with a single NGD stage was designed, at first, and implemented in hybrid microstrip technology; its measurements showed a 75% relative bandwidth and validated the proposed approach. Then, a compact pure phase shifter with a multi-stage NGD cell was designed. It was aimed at meeting specifications in the UWB frequency range, i.e. 3.1-10.6 GHz (110% relative band). Over this band, the corresponding simulation results showed a constant transmission phase of -45°±3°, an insertion gain from 2 to 5.5 dB and insertion losses better than 9 dB.

©Copyright 2008 European Microwave Association http://www.eumwa.org/en/publications/international-journal/journal.html; International audience; This paper proposes and describes in details the synthesis, design and implementation of two different active topologies exhibiting negative group delay (NGD) in different frequency bands. With the first of them, gain and NGD in microwave frequency band are simultaneously achieved; the basic cell consists in a field effect transistor (FET) cascaded with a shunt RLC series network. The second topology brings also gain and NGD but is particularly dedicated to baseband signals; this circuit is also built with a FET; but this time in feedback with an RL series network. For both approaches, analytical formulas demonstrating the existence of gain and NGD are proposed together with details about the associated equations, at first for a single cell and then for multi-stage circuits. After implementation of each topology in a two-stage configuration, the results from experiments in frequency-domain are carefully compared to those from simulations; the same thing is done in time-domain for the baseband-dedicated device. Time-domain simulations and measurements highlight the high capability of both topologies to compensate or control various dispersive effects. Indeed for both circuits, in case of Gaussian-pulse or -modulated signal, the maximum of the output signal exhibits a time advance compared to the input one of respectively more than 40% and 60% of the standard devia-tion of the input signal. Moreover, this high relative time-advance is obtained with gain and a pulse compression phe-nomenon

Triple jump is a traumatic discipline which predisposes athletes to hamstring strains, groin pain and tendinopathies. Sports use prevention to reduce injuries incidence. However, there are none injury program in track and field. Methods : A review of the literature was made to identify existing prevention programs for frequent injuries in triple jump. Results : 6 randomised controlled trial were analysed including 3 studies on hamstring strains, 2 studies on groin injuries and 1 study on tendinopathies. Each article examines the effect of the program on the incidence of the injury concerned Discussion-Conclusion : Nordic Hamstring Exercise (NHE) et Copenhagen Adduction Exercise (CA) have been shown to be effective in improving the physical condition of athletes and reducing the incidence of hamstring strains and groin injuries. Regarding tendinopathies, no conclusive results have been put forward. NHE and CA can be proposed in prevention to triple jumpers.; Le triple saut est une discipline traumatisante de l'athlétisme et prédispose les athlètes aux lésions des ischio-jambiers (IJ), aux blessures à l’aine et aux tendinopathies. La prévention est utilisée dans le sport afin de diminuer l'incidence des blessures. Certains protocoles ont été élaborés pour certains sports. Cependant, aucun protocole n’a été validé en athlétisme. Méthodes : une revue systématisée a été réalisée pour identifier les programmes de prévention existants dans les pathologies les plus fréquentes au triple saut. Résultats : 6 essais contrôlés randomisés ont été analysés comprenant 3 études sur la lésion des IJ, 2 études sur les blessures à l’aine et 1 étude sur les tendinopathies. Chaque article étudient l’effet du programme sur l'incidence de la blessure concernée.Discussion-Conclusion :le Nordic Hamstring Exercise (NHE) et le Copenhagen Adduction Exercise (CA) ont montré leur efficacité dans l'amélioration de la condition physique des athlètes et la diminution de l'incidence des lésions des IJ et des blessures à l’aine. Concernant les tendinopathies, aucun résultat concluant n’a été mis en avant. Le NHE et le CA peuvent être proposé aux triples sauteurs .

The incidence of traumatic brain injury in Brittany is one of the highest in France. Throughout his care pathway, the patient benefits from physical conditioning, however, no recommendation is given to the physiotherapist. The aim of this study is to identify the interests and modalities for carrying-out physical conditioning for patient who have suffered from traumatic brain injury in Brittany. Method : a qualitative study has been carried out through semi-structured interviews with physiotherapists of rehabilitation center or who had an independent practice. Results : the results indicated that modalities of physical conditioning depended on patient’s motor skills. Activities on ergometers was the most used, their implementation methods were varied and no specific protocol for patients who suffered from traumatic brain injury was used. Ecological activities, muscle strengthening and circuit training were also identified. In independent practice, professionals and modalities were not exactly similar. The main interests identified by professionals were the improvement of physical fitness, well-being and socio-professional integration. Discussion : all the professionals interviewed felt that there is a lack of recommendations in order to propose the most appropriate exercise for the patient who suffered from traumatic brain injury. This study reveals that many beneficial effects are observed by the professionnals but they need for more recommendations in order to propose the most effective treatment. This study opens the way for future researches which could propose a protocol adapted to the characteristics of this population.; L’incidence du traumatisme crânien en Bretagne est l’une des plus importantes de France. Tout au long de son parcours de soins, le patient bénéficie de ré-entraînement à l’effort, cependant aucune recommandation n’est établie sur ce sujet. L’objectif de ce travail est d’identifier les intérêts et les modalités de la mise en œuvre du ré-entraînement à l’effort pour les patients traumatisés crâniens bretons. Méthode : une étude qualitative a été réalisée par des entretiens semi-directifs auprès de masseurs-kinésithérapeutes exerçant en centres de rééducation bretons et en libéral. Résultats : les résultats ont montré que la mise en œuvre du ré-entraînement à l’effort dépend principalement des capacités motrices du patient. Les activités sur ergomètre sont les plus utilisées, leurs modalités de mise en œuvre sont variées et aucun protocole spécifique au patient traumatisé crânien n’est utilisé. Les activités fonctionnelles, le renforcement musculaire et le circuit training font également partie du ré-entraînement à l’effort. En libéral, les acteurs du ré-entraînement et les modalités de mise en œuvre peuvent différer. Les principaux intérêts identifiés par les professionnels sont l’amélioration de la condition physique, du bien-être et de la réintégration socio-professionnelle du patient. Discussion : Les résultats montrent que des effets bénéfiques sont observés, néanmoins tous les professionnels interrogés ressentent le besoin de recommandations afin de proposer le traitement le plus efficace. De futures recherches permettraient de définir un protocole spécifique à cette population.

Type 2 diabetes is a biologic, societal and economic burden. Thus, research on the most efficient exercice modality is essential for the physiotherapist to reduce morbidity and mortality in this population. Aims. The purpose of this study is to assess the effectiveness of high-intensity interval training (HIIT) compared with moderateintensity continuous training (MICT) on glycemic control and cardiorespiratory fitness in patients with type 2 diabetes (T2D). Methods. A systematic literature search was perfomed on electronic databases PubMed (MEDLINE), Cochrane Library, Scopus and PEDro during March 2020. Articles were included based upon the following criteria: HIIT was compared with MICT on adults participants who were clinically diagnosed with T2D, outcomes that included glycemic control (hemoglobin A1c, insulin resistance HOMA-IR), cardiometabolic risk factors (Body Mass Index, waist circumference, blood pressure, blood lipid profile), cardiorespiratory fitness (VO2max) were mesured at baseline and post-intervention. The risk of bias was defined by CONSORT 2010 statement. Results. A total of 8 trials involving 279 patients were included in our study. HIIT induced a significant increase in VO2max compared with MICT. Regarding changes in HbA1c and BMI of patients, HIIT showed a tendancy of a greater improvement than MICT. No significant differences were found between this two exercice modalities considering the outcomes insulin resistance, anthropometric parameters, blood pressure and lipid control. Conclusions. The results of this review suggest that HIIT is a therapy with at least equivalent benefit to MICT and may induced more positive effects in patients with T2D. HIIT is a time-efficient strategy and should be considered by physiotherapists when prescribing exercise interventions for people living with type 2 diabetes.; Le diabète de type 2 est une pandémie sanitaire, sociétale et économique. Ainsi, est-il essentiel pour le Masseur Kinésithérapeute d'utiliser le mode d'exercice le plus efficace pour réduire la morbidité et la mortalité dans cette population. Objectifs. L’objectif de cette étude est d’évaluer l’efficacité du « high-intensity interval training » (HIIT) comparé au « moderateintensity continuous training » (MICT) sur le contrôle glycémique et les paramètres cardio-respiratoires chez les diabétiques de type 2 (DT2). Méthodes. Une revue de littérature a été effectuée sur les bases de données PubMed (MEDLINE), Cochrane Library, Scopus et PEDro en Mars 2020. L’inclusion des articles se réfère aux critères suivants : le HIIT est comparé au MICT chez des adultes DT2, les résultats comprenant le contrôle glycémique (hémoglobine A1c, insulino-résistance HOMA-IR), des facteurs de risques cardio-vasculaires (Indice de Masse Corporelle, circonférence de la taille, tension artérielle, profil lipidique), la capacité cardiorespiratoire (VO2max) ont été mesurés en pré et post-intervention. Le risque de biais a été défini selon la ligne directrice CONSORT 2010. Résultats. Au total, 8 essais ont été inclus dans notre étude, pour un total de 279 patients. Le HIIT augmente plus significativement la VO2max par rapport au MICT. En ce qui concerne les changements de l’HbA1c et de l’IMC chez les patients, une tendance à la supériorité du HIIT par rapport au MICT semble se dessiner. Aucune différence significative n’a été constatée entre les deux modalités d’exercice sur les résultats de l'insulino-résistance, les données anthropométriques, le profil tensionnel et lipidique. Conclusions. Les résultats de cette revue de littérature suggèrent que le HIIT est une thérapie au moins équivalente au MICT et pourrait entraîner des bénéfices supérieurs chez les DT2. Le HIIT est une stratégie moins chronophage qui devrait être considérée par les physiothérapeutes lors de programmes d’activité physique adaptée pour les personnes atteintes de diabète de type 2.

This thesis, conducted at Lab−STICC as part of the ANR MUFRED project, focuses on the study, the design and the development of reconfigurable microwave devices based on vanadium dioxide (a metal-insulator transition material). This multidisciplinary project – from material deposition and study to the design and characterization of RF devices by way of optical control – aims to demonstrate the VO2 performances as a tuning element for fast (about ten nanoseconds) to ultra-fast (about hundred picoseconds) switching. With this aim in mind, this work begins with a characterization of vanadium dioxide as a tuning element before integrating it into reconfigurable RF devices. Thus, the first VO2 based switches, SPST, SP2T and SP4T are designed for control of the metal-insulator transition with an electrical or optical command. These switches are subsequently used in the design of reconfigurable 1-bit (relative phase shift of 0° and − 45°) and 2-bits (relative phase shift of 0°, − 90°, − 180° and − 270°) switched lines True Time Delay phase shifters.Then this study focuses on the proof-of-concept targeted by the MUFRED project, i.e. a reconfigurable phased array antennas based on VO2 switches. The performances of each RF blocks involved in its design are described, presented and analyzed.The first demonstrators carried out make it possible to foresee prospects for improvement in the short and long term.; Ce travail de thèse, réalisé au Lab−STICC, dans le cadre du projet ANR MUFRED, porte sur l’étude, la conception et le développement de dispositifs hyperfréquences reconfigurables à base de dioxyde de vanadium (matériau à transition isolant-métal). Ce projet, multidisciplinaire – allant du dépôt et l’étude du matériau à la conception et la caractérisation de dispositifs RF en passant par une commande optique – vise à démontrer les performances du VO2 en tant qu’élément d’accord pour une commutation rapide (une dizaine de nanosecondes) à ultra-rapide (une centaine de picosecondes, selon la littérature). Pour ce faire, ce travail débute par une caractérisation du dioxyde de vanadium en tant qu’élément de commutation avant de l’intégrer dans des dispositifs reconfigurables. Ainsi, les premiers commutateurs SPST, SP2T et SP4T à base de VO2 sont conçus pour un contrôle de la transition isolant-métal par commande électrique et optique. Ces commutateurs sont par la suite utilisés dans la conception de déphaseurs reconfigurables 1-bit (déphasage relatif de 0° et − 45°) et 2-bits (déphasage relatif de 0°, − 90°, − 180°, − 270°) de type « True Time Delay » à lignes commutées. La suite du travail porte sur le démonstrateur ciblé par le projet MUFRED, i.e. un réseau d’antennes phasé reconfigurable à base de commutateurs de VO2. Les performances de chacun des blocs RF intervenant dans sa conception sont décrites, présentées et analysées. Les premiers démonstrateurs réalisés ont permis d’envisager des perspectives d’amélioration à court et long terme.

This thesis, conducted at Lab−STICC as part of the ANR MUFRED project, focuses on the study, the design and the development of reconfigurable microwave devices based on vanadium dioxide (a metal-insulator transition material). This multidisciplinary project – from material deposition and study to the design and characterization of RF devices by way of optical control – aims to demonstrate the VO2 performances as a tuning element for fast (about ten nanoseconds) to ultra-fast (about hundred picoseconds) switching.With this aim in mind, this work begins with a characterization of vanadium dioxide as a tuning element before integrating it into reconfigurable RF devices.Thus, the first VO2 based switches, SPST, SP2T and SP4T are designed for control of the metal-insulator transition with an electrical or optical command. These switches are subsequently used in the design of reconfigurable 1-bit (relative phase shift of 0° and − 45°) and 2-bits (relative phase shift of 0°, − 90°, − 180° and − 270°) switched lines True Time Delay phase shifters.Then this study focuses on the proof-of-concept targeted by the MUFRED project, i.e. a reconfigurable phased array antennas based on VO2 switches. The performances of each RF blocks involved in its design are described, presented and analyzed.The first demonstrators carried out make it possible to foresee prospects for improvement in the short and long term., Ce travail de thèse, réalisé au Lab−STICC, dans le cadre du projet ANR MUFRED, porte sur l’étude, la conception et le développement de dispositifs hyperfréquences reconfigurables à base de dioxyde de vanadium (matériau à transition isolant-métal). Ce projet, multidisciplinaire – allant du dépôt et l’étude du matériau à la conception et la caractérisation de dispositifs RF en passant par une commande optique – vise à démontrer les performances du VO2 en tant qu’élément d’accord pour une commutation rapide (une dizaine de nanosecondes) à ultra-rapide (une centaine de picosecondes, selon la littérature). Pour ce faire, ce travail débute par une caractérisation du dioxyde de vanadium en tant qu’élément de commutation avant de l’intégrer dans des dispositifs reconfigurables.Ainsi, les premiers commutateurs SPST, SP2T et SP4T à base de VO2 sont conçus pour un contrôle de la transition isolant-métal par commande électrique et optique. Ces commutateurs sont par la suite utilisés dans la conception de déphaseurs reconfigurables 1-bit (déphasage relatif de 0° et − 45°) et 2-bits (déphasage relatif de 0°, − 90°, − 180°, − 270°) de type « True Time Delay » à lignes commutées.La suite du travail porte sur le démonstrateur ciblé par le projet MUFRED, i.e. un réseau d’antennes phasé reconfigurable à base de commutateurs de VO2. Les performances de chacun des blocs RF intervenant dans sa conception sont décrites, présentées et analysées.Les premiers démonstrateurs réalisés ont permis d’envisager des perspectives d’amélioration à court et long terme.

Breast cancer, one of the primary causes of women mortality worldwide, can be effectively treated if detected at its early stage. Microwave Imaging (MWI), an emerging technique, promises to complement the currently used diagnostic modalities.It is safe, non-ionizing and potentially inexpensive, thus possessing key features to make it a good candidate for frequent and mass screenings.This thesis summarizes the results of an innovative research conducted on a microwave system for breast tissue screening.A first direct frequency detection technique is proposed using a compact HFA antenna inside cavity specifically designed for use in direct contact with the breast. The simulations results are analyzed and compared to measurements made at CHRU of Brest, which validated a dispersive breast phantom model and demonstrated the limits of this first technique.A second UWB approach is proposed in which a study of the electric field distribution inside the model is conducted for two types of UWB antennas dedicated to use in direct skin contact, a monopole and a directive Vivaldi, all two inserted into a cavity.This comparative study has highlighted the interest of using a directional antenna for this application.Finally, the thesis focuses on time domain study using two configurations of antennas, a single-static configuration and another bi-static to study the possibility of tumor detection and image reconstruction and justifying the development of an antenna system whose objective is to focus the maximum energy in the breast to increase the probability of detection.; Le cancer du sein, l'une des principales causes de mortalité féminine dans le monde, peut être traité avec plus d’efficacité s'il est détecté à un stade précoce. L'imagerie micro-ondes (MWI), technique émergente, apparait comme prometteuse pour compléter les méthodes de diagnostics actuelles. Elle est non-ionisante et potentiellement peu coûteuse, possédant ainsi des caractéristiques clés pour être un bon candidat pour la détection de masse et pour un dépistage fréquent. Cette thèse résume les résultats d'une recherche novatrice menée sur un système micro-onde visant au dépistage dans les tissus mammaires. Une première technique de détection fréquentielle directe est proposée en utilisant une antenne compacte HFA mise en cavité spécifiquement conçue pour une utilisation en contact direct avec le sein. Les résultats de simulations sont analysés et comparés à des mesures faites au CHRU à Brest, ce qui a permis de valider un modèle fantôme dispersif du sein mais aussi de mettre en évidence les limites de cette 1ère technique. Une 2ème approche ULB est proposée dans laquelle une étude de la distribution du champ électrique à l’intérieur du modèle est menée pour deux types d’antennes ULB dédiée à une utilisation en contact direct de la peau, un monopole et une Vivaldi directive, toutes deux insérées dans une cavité. Cette étude comparative a mis en évidence l'intérêt d’utiliser une antenne directive pour cette application. Finalement, une étude élaborée dans le domaine temporel est menée en utilisant deux configurations d’antennes, une configuration mono-statique et une autre bi-statique afin d’étudier la possibilité de la détection tumorale et de la reconstruction d’image. Cette étude permet de justifier la mise au point d’un système antennaire dont l’objectif est de focaliser le maximum d’énergie dans le sein, notamment en concevant les antennes pour une utilisation en contact direct avec la peau pour augmenter la probabilité de la détection des tumeurs cancéreuses.

Anatomo-physiological reminders on the lymphatic system are carried out with the aim of subsequently discussing some drainage implications. Lymphatic drainage is defined and a summary biography for each major actor of lymphatic drainage is performed.Method: An exploration of the literature is carried out around our problematic. Searches are carried out on different search engines. The detailed terms and results are presented in the accompanying tables. A search among the different sources of the found documents is conducted with the aim of widening the scope of the investigation.Discussion: A presentation of the technique or concept of each author is presented. The work of the author is then confronted with the existing literature on the subject. Opening The effectiveness of manual drainage as a whole is discussed and alternative means of fighting edema are opposed to manual lymphatic drainage. The limits of this work are evoked at the end of the part.; Des rappels anatomo-physiologiques sur le système lymphatique sont effectués dans le but de pouvoir par la suite discuter de certaines implications sur le drainage. Le drainage lymphatique y est défini et une biographie sommaire pour chaque grand acteur du drainage lymphatique est réalisée.Méthode : Une exploration de la littérature est effectuée autour de notre problématique. Les recherches sont portées sur différents moteurs de recherches. Les modalités précises ainsi que les résultats sont regroupés dans des tableaux annexes. Une recherche parmi les différentes sources des documents trouvés est conduite dans le but d’élargir le champ d’investigation.Discussion : Une présentation de la technique ou concept de chaque auteur est présentée. Le travail de l’auteur est ensuite confronté à la littérature existante sur le sujet. Ouverture L’efficacité du drainage manuel dans son ensemble est discutée et les moyens alternatifs de lutte contre l’oedème sont opposés au drainage lymphatique manuel. Les limites de ce travail sont évoquées en fin de partie.

Chronic pain frequently affects a portion of the general population. The effect of chronic pain on the patient's everyday life are considerable and greatly impact their quality of life. A bio-psycho-social approach is essential to addressing chronic pain disorder. Physiotherapists are able to rely on approaches such as cognitive-behavioral therapy (CBT) to handle this type of multi-dimensional pathology. Through this work, we attempt to determine whether mindfulness meditation, a type of CBT performed as the Mindfulness-Based Stress Reduction program (MBSR), can help with chronic pain. In order to do this, we reviewed the literature available on this topic taking as criteria pain, functioning capacities, quality of life, anxiety, and depression. After reviewing 6 selected articles, we were not able to demonstrate the success of the program MBSR based on the aforementioned 5 criteria. To this day, the scientific scholarly literature on this topic doesn't-allow us to affirm the usefulness of mindfulness meditation on chronic pain.; La douleur chronique est une affection fréquente dans la population générale. Les répercussions sur la vie quotidienne du patient sont importantes et affectent grandement sa qualité de vie. L’approche bio-psycho-social de la maladie et essentielle dans la prise en charge de cette affection. Des approches comme les thérapies cognitivo-comportementales (TCC) sont des thérapies auxquelles le masseur kinésithérapeute peut faire appel pour ce type de pathologies aux dimensions multiple. Au cours de ce travail, j’ai essayé de déterminer si la méditation de pleine conscience (MPC), qui fait partie des TCC, sous la forme du programme Mindfulness-Based Stress Reduction (MBSR), pouvait avoir un intérêt pour la douleur chronique. Pour cela, j’ai réalisé une revue de la littérature sur ce sujet, en prenant pour critères de jugement la douleur, les capacités fonctionnelles, la qualité de vie, l’anxiété et la dépression. Les résultats, après analyse de 6 articles retenus, n’apporte pas de preuves de l’influence positive du programme MBSR sur ces 5 critères. À ce jour, la littérature scientifique sur le sujet ne nous permet pas d’affirmer l’utilité de la MPC pour la douleur chronique.

Glenohumeral joint's dislocation constitutes the first step toward instability. It handicaps the practice of handball, which is a contact sport. Consequently, it maintains this risk. The trauma caused by luxation associated with the regular practice of this activity creates a lot of specific adaptations limiting neuro-muscular rehabilitation in the handball player who has already undergone a first episode of glenohumeral dislocation which has not been treated surgically. However, many scientific researches have been applied to healthy subjects, not to handball players, or not always involving shoulder instability. The conclusion of this work remains to be modulated.; La luxation gléno-humérale constitue la première étape du passage vers l'instabilité articulaire antérieure. Cette dernière handicape la pratique sportive. Le hand-ball est un sport de contact, par conséquent il alimente ce risque. Les traumatismes engendrés par la luxation associés à la pratique régulière de cette activité créent de multiples adaptations spécifiques limitant la rééducation neuro-musculaire chez le hand-balleur ayant déjà subi un premier épisode de dislocation gléno-humérale non traité chirurgicalement. Cependant, de nombreuses recherches scientifiques ont été appliquées à des sujets sains, non handballeur, ou ne concernant pas toujours l’instabilité d’épaule. La conclusion de ce travail reste donc à moduler.

The use of upper limb in extrem articular positions, repetitive movements and a narrow subacromial space are risk factors for developping supraspinatus tendinopathy. This work aim is to define the influence of humeral head centering in supraspinatus tendinopathy.Method : Starting from a clinical case, using pectoralis major and dorsalis major to lower humeral head, a comparison is realised with other techniques from littérature data.Conclusion : Each of these techniques describes improvement of pain, joint amplitudes and functionnal capacities. However, there is no superiority evidence of a technique compared to another one.; L'utilisation du membre supérieur dans des positions articulaires extrêmes, la répétitivité du geste et la réduction de l'espace sous-acromial sont des facteurs de risque de développement d'une tendinopathie du supra-épineux. Ce travail tente de répondre à la question de l'influence du recentrage actif dans le cadre de tendinopathie du supra-épineux.Méthode : À partir d'un cas clinique utilisant la technique d'abaissement par le grand pectoral et le grand dorsal, une comparaison avec d'autres techniques est réalisée à partir des données de la littérature.Résultats : Chacune des techniques recensées décrivent une amélioration de la douleur, des amplitudes ainsi que des capacités fonctionnelles, sans preuve de supériorité d'une technique par rapport à une autre.

Deconditioning with effort affects a large number of paraplegics, which has an impact on their health. The exercise rehabilitation proposed today presents constraints related to the overuse of the upper limbs and to the prolonged sitting position. Recent technology provides patients with powered exoskeletons for walking. It is therefore interesting to question the cardiorespiratory response associated with this type of walk. Studies show an increase in cardiorespiratory response corresponding to a moderate intensity, recommended minimum intensity to improve fitness according to the American College of Sport Medicine (ACSM). Nevertheless, to date, studies on walking with a motorized exoskeleton have not yet analyzed the impact on the cardiorespiratory system in the long term.; Le déconditionnement à l’effort touche un grand nombre de paraplégiques, ce qui a un impact sur leur état de santé. Le réentraînement à l’effort aujourd’hui proposé présente des contraintes liées à la surutilisation des membres supérieurs et au maintien prolongé de la position assise. La technologie récente met à disposition des patients, des exosquelettes de marche motorisés. Il est donc intéressant de se questionner sur la réponse cardio-respiratoire associée à ce type de déambulation. Les études montrent une augmentation de la réponse cardiorespiratoirecorrespondant à une intensité modérée, intensité minimal recommandée afin d’améliorer la forme physique selon l’American College of SportMedicine (ACSM). Néanmoins, à ce jour les études concernant la marche avec un exosquelette motorisé n’ont pas encore analysé l’impact sur l’appareil cardiorespiratoire à long terme.