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Planar microwave sensors are considered an attractive choice to noninvasively probe the dielectric attributes of biological tissues due to their low cost, simple fabrication, miniature scale, and minimum risk to human health. This paper develops and measures a novel microwave biosensor for non-invasive real-time monitoring of glucose level. The design comprises a rectangular plexiglass channel integrated on a triple-pole complementary split ring resonator (TP-CSRR). The proposed sensor operates in the centimeter-wave range 1-6 GHz and is manufactured using PCB on top of an FR4 dielectric substrate. The sensor elements are excited via a coupled microstrip transmission-line etched on the bottom side of the substrate. The integrated CSRR-based sensor is used as a near-field probe to non-invasively monitor the glucose level changes in the blood mimicking solutions of clinically relevant concentrations to Type-2 normal diabetes (70-120 mg/dL), by recording the frequency response of the harmonic reflection and transmission resonances. This indicates the sensor's capability of detecting small variations in the dielectric properties of the blood samples that are responsive to the electromagnetic fields. The proposed sensor is verified through practical measurements of the fabricated design. Experimental results obtained using a Vector Network Analyzer (VNA) demonstrate a sensitivity performance of about 6.2 dB/(mg/ml) for the developed triple-pole sensor that significantly outperforms the conventional single-pole and other proposed sensors in the literature in terms of the resonance amplitude resolution.

The recent years have seen a surge in interest in determining the dielectric constant of biological tissues in the microwave domain. The tissues can be classified and differentiated without radiation by using a microwave sensor. The atherosclerotic plaque of the carotid artery, which is now predominantly classified by ultrasonography and the CT scanner was not studied yet. Ultrasonography describes the level of echogenicity of the plaques, and proposes that as a representation of the plaque's composition. In this study, a microwave subwavelength resonator was employed to measure 20 carotid artery plaques and compare the results with ultrasound b-mode images. The results of the study show a correlation between the echogenicity levels and the dielectric constant of the tissues investigated. The way in which it will be evaluated in the future is how it compares to other radiological techniques.

International audience; Microwave planar sensors have a great interest in the medical environment due to their ability to measure the bulk dielectric parameters of biological tissues through non-invasive and contact-less sensing properties. Changes of these parameters, which are frequency dependent, can be representative of the pathological state of biological tissues. In this work, an improved prototype of planar sensor based on a microwave ring resonator operating at 1 GHz for the fundamental mode is presented. The objective is to obtain a better sensitivity for measuring high complex permittivity values of materials such as biological tissues, and to obtain higher precision in parameters determination. The performances of two sensors optimized on two different substrates were measured in a frequency range 1–10 GHz; an accurate equivalent electrical model is proposed to reproduce the frequency dependence of the resonators. Characterization of liquids and ex-vivo animal tissues is achieved to evaluate the effectiveness and the performances of the resonator sensor, and results are compared with electromagnetic simulations.

In this article, we propose a planar microwave sensor that consists of four distinct hexagonal-shaped complementary split ring resonators (CSRRs) configured in the honey-cell pattern. The sensor element operating at 1.5 - 3.0 GHz is fabricated on an FR4 dielectric substrate and excited via the microstrip technology in the cm-wave band. The proposed sensor is used as a near-field probe to detect the glucose levels in the blood mimicking aqueous solutions via tracing the frequency shift responses for tested glucose concentrations in the range 70 - 120 mg/dL. The sensor exhibits an excellent resonant frequency sensitivity that excels others in the literature. The sensor sensitivity, reliability and repeatability are demonstrated by the in-lab measurements via a Vector Network Analyzer (VNA).

In this paper, we propose a microwave biosensor that comprises a rectangular plexiglass channel integrated on a triple-pole complementary split ring resonator (TP-CSRR) structure. The sensor operates in the centimeter-band 1 – 6 GHz and is fabricated on top of a thin FR4 dielectric substrate. The sensor element is excited via a coupled microstrip transmission-line etched on the bottom side of the substrate. The proposed CSRR-based sensor is used as a near-field probe to noninvasively monitor the changes in glucose concentrations in the blood mimicking fluid by tracking the amplitude variations of the harmonic transmission resonances at various concentrations. The fluids are loaded inside a channel representing roughly a blood vessel. The proposed sensor is shown to exhibit higher sensitivity performance compared to the conventional single-pole and other similar sensors in the literature. The sensitivity, reliability and repeatability of the proposed sensor are demonstrated by the in-lab measurements using a Vector Network Analyzer (VNA).

Context Microwave sensing appears to be an open wide field to investigate medical applications, such as monitoring of vital signs (temperature, arterial pressure, …), following different kinds of pathologies (cancer, glucose level …) and aid for medical diagnosis. It offers an alternative to determine the dielectric properties of biological tissues through the development of local non-invasive and/or embedded sensors, giving thus a kind of imaging by the dielectric contrast. Moreover, RF communications links between several sensors can be developed to realize “Body Area Networks”. Methods Biological tissues having high dielectric permittivity and losses in the microwave frequency domain (around 1 GHz), a resonant dielectric characterization method is used to obtain a good sensitivity. The experimental setup is based on the measured changes of electrical characteristics of the resonator (resonance frequency and its shift and broadening) when a biological tissue is applied on it. In our case, the sensor is a microstrip ring resonator operating in a two-port configuration at a fundamental frequency of 1 GHz. It consists of a meander loop in order to reduce its dimensions. Besides, an original excitation is proposed leading to small perturbation of the resonator when high dielectric losses material is characterized. This increased greatly the sensitivity of the method to obtain the dielectric properties of the samples. Dielectric parameters are determined by fitting S parameters measurements results with those of simulations using electromagnetic software's (HFSS, CST). Results Several biological tissues of animal origin were measured ex-vivo in the frequency range 0.5–5 GHz. The dielectric parameters obtained by this method are consistent with values proposed in databases or obtained by other researchers. A very good agreement between simulations and measurements is obtained leading to a good extraction of permittivity and losses of the tissues. Conclusions This paper presents an improved microwave sensor, either for reduced dimensions as for sensitivity, able to perform dielectric characterization of material having high complex permittivity such as biological tissues. Experiments and electromagnetic simulations have been achieved on several animal tissues (chicken, beef, pork …), and results are in good agreement with literature. Works are in progress to optimize this sensor as an applicator for medical applications.

Planar microwave sensors are very interesting for health applications, such as the investigation of dielectric properties of biological tissues in a non-invasive and contactless manner. In this paper, three structures of complementary split-ring resonators (CSRRs) coupled to microstrip lines are investigated with ex-vivo characterization of animal tissues. Compared to ring resonators, their main advantage consists in more compact sensors, enabling a better local dielectric characterization of the tissues. The extraction of dielectric parameters is obtained by an optimization process based on a comparison of experimental results with electromagnetic simulations with full-wave three-dimensional (3D) finite element method implemented in HFSS and CST.

International audience; This paper presents the design and performance of a single-ended transimpedance amplifier (TIA) for gigabit passive optical networks (GPON) implementing orthogonal frequency division multiplexing (OFDM) modulation format. The circuit is realized using an industrial GaAs integrated technology. Low power consumption and small chip area are the main challenges in the TIA design. On-wafer characterization in terms of S-parameters, noise figure, gain compression and intermodulation are presented and compared to simulated results showing a good agreement. The TIA is linked with a broadband PIN photodiode and introduced in a radio over fiber (RoF) system. The optical link is simulated in a microwave software and characterized in terms of error vector magnitude (EVM) by varying the radio frequency (RF) input power and the laser bias current.

The authors' research work has for objective the study of a sensor with planar resonator for applications in the non-destructive control. In this context, two approaches were defined. In a first part, a conception, a modeling, a simulation with commercial software (HFSS, CST), a realization and measurements were treated on Rectangular Patch Resonators (RPR). The proposed theoretical analysis is based on the Moment Method (MoM) via the Galerkin's approach, in which three types of entire domain basis functions are used to expand the patch currents. While, the first two types of basic functions involve a set of sinusoidal cavity modes without edge conditions (sbf-wo-ec) and with edge conditions (sbf-w-ec), and in order to incorporate the edge conditions (cp-ec), the third one consists of Chebyshev polynomials combinations with weighting factors. These last ones as well as the Green Dyadic spectral functions are efficiently implanted with compact Fortran 90 codes. Two EM commercial software HFSS and CST was used to validate the proposed RPR prototypes. The exactness of the obtained results is estimated using four prototypes operating near 6 GHz, taking into account only the fundamental mode resonant frequency. The theoretical model is compared with the simulations and the measurement results. The second approach of the authors' work which is developed in this paper is focused on the characterization of biological materials in vitro using the RPR prototypes proposed as applicator in the non-destructive control and the medical domain to find the abnormalities of these tissues such as: eczema, psoriasis, cancer, etc. The authors' center of interest will be managed towards the dielectric properties of the biological material to extract the relative permittivity and the loss factor on several samples (liver, fat, chicken, butter, foie gras, etc.).

This paper presents about non-invasive planar complementary split ring resonators (CSRRs) coupled to microstrip line to measure the dielectric properties of materials and biological tissues. The expectations of health professionals are increasingly turning to less invasive surgical procedures and treatments. In particular, the monitoring of vital parameters (sweat, water in the lungs, etc.) or the evolution of certain pathologies, such as cancer cells, could be observed regularly if suitable devices were developed and could especially replace traditional invasive method. Appropriate miniaturized RF or microwave devices could be an alternative for some medical diagnostic applications. These devices would make it possible to determine the dielectric characteristics of biological tissues, which represent their real pathological states. Thus, it would be possible that dielectric contrast measurements will be able to follow the evolution of pathology, as well as the vital parameters of a patient. The objective of this research is to investigate a prototype biosensor that is suitable for measurements on biological tissues and can be miniaturized to enhance its spatial sensitivity. This work focuses on the design, electromagnetic simulations, and characterization of a new miniaturized biosensor at 2.4 GHz. The ex-vivo experimental results will be shown by measuring the S-parameters of various materials and animal biological tissues. The extraction of the dielectric parameters of these samples is obtained by the measurements of materials.

International audience; In this paper, modeling and experimentation of a Rectangular Patch Resonator (RPR) covered with a dielectric superstrate are investigated. The RPR criteria are established theoretically and experimentally, to be used in future prospects as an electromagnetic (EM) sensor for the characterization of superstrates. The theoretical model is based on the moment method (MoM) via Galerkin's approach, in which three types of basis and testing functions are used. These functions as well as the spectral dyadic Green function are efficiently implanted with compact structured Fortran 90 codes. The EM commercial HFSS and CST Microwave Studio softwares are used to simulate the proposed RPR prototypes. The accuracy of the obtained results is assessed using four prototypes of RPRs operating around 6 GHz, taking into account only the resonant frequency of the fundamental dominant mode. The theoretical model is compared to simulation and measurement results, and very good agreements are observed.

We studied the preference judgment of pictorial images by image experts and naive observers. We first asked image experts to improve pictorial images the way they preferred. Then, we showed the different versions of each image to naive observers and asked them which version they preferred. To enhance an image, an expert divides it into large areas of interest, which mainly correspond to natural colors. To assess their preference judgments, naive observers principally focus on natural colors like sky, skin, or grass when present. A closer analysis of the digital image files showed that the segmentation process used by the experts allows to apply different corrections on the different objects. We used the previous work on memory colors by Yendrikhovskij and we showed that, to enhance an image, an expert moves the color space coordinates of identified zones towards those of memory colors corresponding to the objects being represented. The expert also follows some rules: the corrections must be plausible inside each segment and for the whole image, in relation with the illuminant of the scene. The images are accepted by observers in relation with the presence of memory colors and when the treatment of the whole image seems coherent.

Non-invasive planar complementary split ring resonators (CSRRs) coupled to microstrip line for measuring the dielectric properties of materials and biological tissues are presented in this paper. The expectations of health professionals are increasingly turning to less invasive surgical procedures and treatments. In particular, the monitoring of vital parameters (sweat, water in the lungs, etc.) or the evolution of certain pathologies, such as cancer cells, could be observed regularly if suitable devices were developed and could especially replace traditional invasive method. Appropriate miniaturized RF or microwave devices could be an alternative for some medical diagnostic applications. These devices would make it possible to determine the dielectric characteristics of biological tissues, which represent their real pathological states. It would thus be possible, by means of dielectric contrast measurements, to follow the evolution of pathology as well as the vital parameters of a patient. The objective of this research is to produce a prototype biosensor that is suitable for measurements on biological tissues and that can be miniaturized to enhance its spatial sensitivity. This work focuses on the design, electromagnetic simulations and characterization of a new miniaturized biosensors operating between 1 and 10 GHz. The ex-vivo experimental results will be shown by measuring the S-parameters of various materials and animal biological tissues. The extraction of the dielectric parameters of these samples is obtained by the measurements of materials

International audience; This paper has for objective to explore the study of a sensor based on a rectangular planar resonator (RPR) for applications to Non-destructive Evaluation (NDE). In this context, conception, modeling, simulation and realization have been made on rectangular structures with an anisotropic substrate and an isotropic superstrate. The theoretical model is based on the moment method (MoM) via Galerkin's approach, in which three types of basis and testing functions are used. These functions as well as the spectral dyadic Green function are efficiently implanted on compact structured Fortran 90 codes. The accuracy of the obtained results is assessed using four prototypes of RPRs operating around 6 GHz, taking only into account the Resonant Frequency (RF) of the fundamental dominant mode. The theoretical model is compared to simulation and measurements results and shown very good agreements. The RPR criteria are established theoretically and validated experimentally with two electromagnetic commercial softwares (HFSS and CST); to be used in future prospects as an electromagnetic (EM) sensor for the characterization of superstrates.

International audience; This paper presents performance comparisons of systems based on Radio over Fiber (RoF) links with an intensity modulation-direct detection technique (IM-DD). Measurement and simulation results on systems using direct and external modulations with a MB-OFDM signal are presented. The first band group of the centimeter-wave ultra wideband with a 16 QAM advanced modulation format and a data rate of 480 Mb/s is used to validate system simulation. The error vector magnitude (EVM) and the bit error rate (BER) for digital modulated signals enable to quantify the quality of the received signal. The system simulations are performed with developed equivalent electrical models of optoelectronic components. These models including noise and nonlinearity are validated with static/dynamic responses and noise measurements. Global system simulation is achieved by a co-simulation method in ADS combining envelope simulator and data flow controller for digital signals.

The concept of using rectangular patch resonator (RPR) sensors for microwave characterization of biological materials is the non-invasive nature of the technique. It is being used extensively for the complex dielectric properties measurements of materials in the microwave region. Applications in microwave systems, the dielectric substrate and superstrate are made with low loss materials for the best operation. When RPR is used as the sensor, the superstrate is made with the unknown material under test; the objective is then to extract from measurements the dielectric parameters of this material. An accurate modeling of structures, associated with measurement data, is required to obtain, right values of dielectric parameters of unknown material by solving the inverse problem. Our research was established on the implementation of RPR prototypes, in order to be used as a biosensor for non-invasive testing and medical applications to characterize the dielectric properties of various biological materials. Our measurements showed that the complex dielectric properties obtained by this technique are in good agreement with simulations using C.Gabriel & al comparative data.

A multispectral imaging system enabling biological tissue identifying and differentiation is presented. The measurement of β(λ) spectral radiance factor cube for four tissue types (beef muscle, pork muscle, turkey muscle and beef liver) present in the same scene was carried out. Three methods for tissue identification are proposed and their relevance evaluated. The first method correlates the scene spectral radiance factor with tissue database characteristics. This method gives detection rates ranging from 63.5 % to 85 %. The second method correlates the scene spectral radiance factor derivatives with a database of tissue β(λ) derivatives. This method is more efficient than the first one because it gives detection rates ranging from 79 % to 89 % with over-detection rates smaller than 0.2 %. The third method uses the biological tissue spectral signature. It enhances contrast in order to afford tissue differentiation and identification.

International audience; This work focuses on development of a multispectral imaging system for intraoperative diagnosis aid purpose. The system should be able to identify and differentiate biological tissues in an operative scene, by measurement of their spectral reflectance in the visible and the near infrared wavelength range. Multispectral images in the near infrared may be used to see in depth and to identify buried tissues. The paper introduces a multispectral imaging device we have developed and validated by in vitro measurements. In vivo tests need specific measurements protocol and should be carried later. The imaging system is composed by one calibrated CCD camera, by one optical device with three holographic gratings and by halogen light source. Multispectral images produced by this system are obtained according to the 0°/45° CIE standard geometry. In order to validate this system to evaluate measurements fluctuations several tests were made on different muscle slices. This study showed a fluctuation of 20% to 30% on the same slice of a given tissue. This large error rises from the intrinsic, complex and non homogeneous nature of biological tissues. It represents a great limitation to this spectral measurements technique and affects its ability in terms of tissues spectral reflectance factor evaluation.

International audience; The great interest of optical fiber links in communicating systems especially in ultra-wide band (UWB) communications has grown up in the last decade and requires co-simulation for mixed circuits design exploiting both optical and microwave domains. In this paper, we report an original modeling method of an electro-absorption modulator associated with a distributed-feedback laser to simulate an optical transmitter of an UWB over fiber system. Large signal optoelectronic device models can be developed and implemented in a high-frequency simulator, such as advanced design system-Ptolemy to analyze the performances of fiber radio links and study the impact of the transmitter characteristics. This specific simulation way, taking into account precisely electrical characteristics of both electrical and optical circuits, links two different frequency domains by coupling electrical and optical modules in the same system simulator. Therefore, a complete simulation of an UWB multi-band orthogonal frequency division multiplexing signal transmission over fiber with an external modulator is investigated.

International audience; Predicted results and measured data of an original optically switched oscillator realised on GaAs MMIC technology are presented. The photoconductive effect within the semiconductor substrate is exploited to induce, by application of a suitable optical power on a microwave photoconductive switch, the oscillating behaviour of an active device at a frequency of 4.9 GHz. Modulation-intensity effect of an optical signal on free-running frequency and an output power are also analysed. This oscillator could be easily integrated within communication systems to achieve high data rate amplitude and phase modulation of microwave carriers.

This paper reports on microwave photonics design and characterization of optically-controlled MMIC oscillator. Microwave photoconductive switches (MPCS) design methodology under continuous, intensity-modulated and pulsed optical control has led to microwave predictions of an oscillating device in GaAs integrated technology, under these optical control formats. Microwave oscillations at a frequency of 5 GHz during 2 ns have been experimentally achieved thanks to device illumination using fs optical pulses at 80 MHz repetition frequency.

Many new proposals are continually published in the halftoning domain. Alas, the demonstration of the interest of the proposed methods is often limited to a few favourable tests for the proposed methods, and images showing the defects of the other halftoning methods. The halftoning community needs to be able to compare a halftoning method with the innovations that appear in this domain. A complete and measured evaluation of quality is necessary through to a well defined set of test images and metrics to evaluate the algorithm. This paper proposes a protocol for the quality assessment of digital halftoning algorithm that can be used to compare one algorithm to another. It discusses the assessment of halftoner quality. It analyzes the perceived image quality concepts and defines the technical criteria that a good halftoner must match. A first sketch of a simple quality assessment protocol is proposed. It is composed of test images and quality metrics. This protocol could be used to provide new proposed halftoning algorithms with objective results.

Theoretical and experimental study of photoconductive optically controlled microwave oscillator on GaAs substrate is described. This oscillator gives a 5 GHz output signal if a suitable light power is applied (ON state) and without illumination oscillations disappear (OFF state). The light is applied on the 50mum microstrip photoswitching device which presents different impedances with several light intensities

Microwave photonics contributes through ultrafast devices to the processing of high data rates. In this area, microwave photoconductive switches (MPCSs) in integrated technology have proved their performances to control the transmission of high frequency signals in complex systems. Their ability to switch microwave signal phase and magnitude is fully defined by a complex frequency-dependant ON/OFF ratio R ON/OFF determined from S-Parameters measurements in microwave frequency domain. This paper reports on a new design of MPCSs to be used, after realization and evaluation, as a basic block in optically controlled MMIC devices for application in high frequency samplers or phase shifters.

There are two main families among the halftoning methods: halftoning by masking (i.e. blue noise masking) and error diffusion halftoning. The first family produces neither "worms" nor defects related to stationary regimes but has a limited spatial bandwidth. The error diffusion halftoning method is characterized by a very broad spatial bandwidth allowing good rendition of very thin lines and patterns but this method presents sometimes unpleasant worms or stationary regimes. These methods are complementary with respect to quality. In this paper we propose a halftoning algorithm in black and white, derived from the error diffusion of Floyd Steinberg. By using a new threshold modulation, our new method combines the advantages of both masking and error diffusion algorithms. In order to evaluate our algorithm we defined a set of test images allowing the evaluation of the critical points of quality for the technical imagery: graininess, patterning and spatial bandwidth. The rendering of the presented algorithm has low graininess, no unpleasant patterning and broad spatial bandwidth.

Color imaging systems still use a combination of conventional photo-detectors and RGB optical filters for color measurement. This entails many limitations to the color sensor performances. We reported that buried junction color detectors give good alternatives to overcome these limitations. However, successful design of color sensors using these detectors requires an accurate knowledge of their behaviors. Unfortunately, circuit simulators do not provide models for these devices. In order to make the designer task more flexible, an optoelectronic library is developed under CADENCE design tool. It consists of some optoelectronic elements such as Buried Double pn Junction (BDJ) detector and a set of optical sources. This allows the designer to choose an optical stimulus with a specific spectral distribution and also to select the total power incident on the BDJ surface. The library is obtained by implementing, in Spectre simulator, the behavioral models of the optoelectronic elements. The models are written using Verilog-A language. Simulations of the BDJ spectral response and dark currents give a good agreement with experimental data. We also note the absence of convergence errors or mathematical faults during DC and transient simulations of active pixel sensor architectures. These results confirm the robustness of the optoelectronic library.

An ultra-high definition multi-spectral scanner (able to scan from the ultraviolet to infra-red spectra) with a homogeneous lighting system is being developed for the direct fast capture of images of paintings. The multi-spectral images are calibrated using the CRISATEL pigment colour charts designed specifically for painting materials. Spectrometric analysis of the varnish layers allows the effect of aged or glossy varnish to be corrected on the digital image. Simulation of varnish removal and comparison between the simulated image and ... 295 300

We have recently developed in our laboratory a new integrated photodetector called BDJ. This detector allows determination of the wavelength of a monochromatic light. It was used to realize colorimetric applications. To develop such optoelectronic systems or microsystems we need simulations of their electronic behavior. Simulators like SPICE give in their libraries models for electrical components but not for optoelectronic components like photosensors or optic system. So we have developed a SPICE model to simulate the BDJ detector behavior and the optic source response. This model was implemented under SPICE and to illustrate its use, we have chosen to simulate two colorimetric applications developed in our laboratory; the first one allows determination of iron concentration and the second of the pH of solutions. In these applications, the optic system is composed of a light source (in practice Led's), and of a tube containing a liquid sensitive to the incident light wavelength; the transmission coefficient of the liquid depends on iron concentration in the first case and on reactive concentration and pH in the second case. Behavioral models of this optic system were included in the BDJ detector SPICE model. So we can obtain photocurrents ratio versus iron concentration or pH and reactive concentration. This system was simulated with an electronic associated circuit. This circuit is a classic analog circuit including several operational amplifiers. The optoelectronic system with associated circuit was described and simulated under SPICE and gives good results in comparison with measurements.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Resume — L’utilisation de l’effet photoconducteur pour controler des circuits integres microondes est ici exploitee. Le controle est effectue sur un composant passif : un gap microruban photocommutateur qui presente l’avantage de pouvoir etre integre aisement dans une technologie de circuits MMIC industrielle. Nous avons developpe un modele de photocommutateur nonlineaire base sur les mesures pour la conception d’un oscillateur MMIC a 5 GHz fabrique selon la technologie UMS PH25 sur GaAs. Cet oscillateur delivre un signal lorsque le gap, place sur la source du transistor, est eclaire (etat ON) et ne fonctionne plus lorsque le gap n’est pas eclaire (etat OFF). Ce fonctionnement repose sur la variation de l’impedance equivalente du gap en fonction de la puissance de l’eclairement. Les premiers tests de ce circuit opto-microonde sont presentes. Mots cles: effet photoconducteur, gap microruban, oscillateur microonde.

Cette thèse traite de l'aspect radio sur fibre dans le contexte du réseau d'accès et du réseau privatif. Elle nous a permis de comprendre les problèmes liés à une transmission radio sur fibre. Par la suite, nous avons réalisé des bilans de liaison radio sur fibre pour les systèmes suivant UMTS, WiMAX WiFi et UWB afin d'avoir une première idée sur les architectures réalisables. Puis nous avons réalisé et validé les modèles équivalents en bande de base des équipements optiques pour une transmission radio sur fibre. Ces modèles permettront d'ajuster et d'optimiser les signaux radio en tenant compte de la dégradation du signal lié à l'optique. Enfin, nous avons proposé des architectures radio sur fibre innovantes qui permettent de mutualiser les infrastructures d'accès optiques.; No data

Cette thèse traite de l'aspect radio sur fibre dans le contexte du réseau d'accès et du réseau privatif. Elle nous a permis de comprendre les problèmes liés à une transmission radio sur fibre. Par la suite, nous avons réalisé des bilans de liaison radio sur fibre pour les systèmes suivant UMTS, WiMAX WiFi et UWB afin d'avoir une première idée sur les architectures réalisables. Puis nous avons réalisé et validé les modèles équivalents en bande de base des équipements optiques pour une transmission radio sur fibre. Ces modèles permettront d'ajuster et d'optimiser les signaux radio en tenant compte de la dégradation du signal lié à l'optique. Enfin, nous avons proposé des architectures radio sur fibre innovantes qui permettent de mutualiser les infrastructures d'accès optiques.; No data