Search

International audience; This paper describes the design and the optimization in terms of phase noise of a fully integrated NMOS Voltage Controlled Oscillator (VCO) using a 0.25 μm BICMOS SiGe process. A three-dimensional phase noise analysis diagram and a graphical optimization approach is presented to optimize the phase noise of the VCO while satisfying design constraints such as tank amplitude, power dissipation, tuning range and start up conditions. At 2.5 V power supply voltage, the optimized VCO features a simulated phase noise of -118 dBc/Hz at 1 MHz frequency offset from a 6.12 GHz carrier. The VCO is tuned from 6.1 GHz to 7.9 GHz with a tuning voltage varying from 0 to 2.5 V, and a power dissipation of only 7.4 mW.

This article presents a real-life application for the extremal harmonic active control of power [1] applied on a hybrid engine setup. The active control was adapted for a hybrid powertrain constituted of a one-cylinder diesel engine coupled with a permanent magnet synchronous machine. The problem was formulated in the harmonic domain and the control objective was to extremalize energetic criterions. Three criterions were considered: minimizing the speed ripple of the engine, maximizing the mechanical reactive power (mechanical impedance adaptation) and maximizing the active electric power for energy harvesting. The results show that, for the first and second orders of the ripple, speed oscillations can be completely cancelled and reactive power and active power can be optimized on-line. The implicit extremal controller converged rapidly, remaining stable even when the mean engine speed changed abruptly. These results confirm the robustness and the applicability of the extremal harmonic active control for industrial applications.

This paper deals with the design and application of eight-linear voltage controllers that provide satisfactory voltage control performance in the presence of unknown load variation. The controller synthesis is based on the synchronous generator (SG) modeling strategy and the feedback control linearization method. Two models are presented. The first one takes into account a fixed load connected to the SG. The second model considers an unknown load. This consideration permits the design of a robust controller as regards the load variation. In addition, the linearization of the feedback control is established using a single-input-single-output controller and a multi-input-single-output (MISO) controller. The MISO solution represents a linearization method without any approximations. To validate the efficiency of each solution, the controllers are developed by using the H∞ method and implementation in a real-time domain is then performed.

In this paper, the problem of deriving a dynamical model of a cross flow heat exchanger is considered. In order to take into account the dependency of the system's dynamics on the hot and the cold mass flow rates in an explicit way, an input-output linear parameter-varying (LPV) model is used. A local approach composed of three steps is carried out to identify this LPV model. A parameter estimation scheme is introduced in which cost functions are minimized by using specific nonlinear programming methods. In this study, a finite volume physical model simulator is exploited to simulate and to generate the data. Simulations are performed to demonstrate the benefits of the suggested approach.

In this study, the authors present an identification procedure of a non-linear thermal system that exhibits a diffusive interface. Indeed, the system deals with heat conduction in a homogeneous material through a wall. Heating front face temperature dynamics when random heat flux is applied to the wall's front face area are considered. If the thermophysical properties of the material depend on the temperature, the heat equation is not linear anymore. Hence, in order to explicitly take into account the dependence of the system dynamics on the temperature, a fractional continuous linear parameter-varying model is used and determined thanks to a local approach composed of two steps. First, the authors show that for small heating temperature variations, the heat diffusion can be modelled with the help of a local fractional model based on a fractional integrator operator of order (1/2), which acts only over a limited spectral band. The transfer function parameters of this model are estimated thanks to an output-error technique at different initial temperature-operating points. Secondly, the transfer function parameters dependence with respect to the initial temperature of the material is obtained by direct polynomial interpolation. Simulations using ARMCO iron are used to demonstrate the performances of the proposed local approach.

Mastery of the initial conditions of fractional order systems remains an open problem, in spite of a great number of contributions. This paper proposes a solution dedicated to linear fractional differential equations (FDEs), which is based on an equivalence principle between the original system and an exactly equivalent infinite dimensional ordinary differential equation (ODE). This equivalence principle is derived from the fractional integration operator concept and the frequency distributed state space model of this operator. Thanks to this principle, the FDE initial conditions problem is converted into a conventional ODE initialization problem, however with an infinite dimensional state vector. Practical FDE initialization is performed using an observer based technique applied to the equivalent ODE; a numerical example demonstrates the efficiency of this approach.

In this article, we present an accurate characterization of the RF LDMOSFET transistors for the extracting of the large-signal model. They are generally available encapsulated in package. A measurement of the package parameters are made only by removing the semiconductor chip. The transistor is then characterized by conventional method. The same component can be used in the desired function, thereby avoiding the technological dispersions. The LDMOSFET transistor used is a BLF2043F (NXP semiconductors). To validate our method, we implemented a 2.5-GHz 10-W power amplifier. The measured and simulated results match very well. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:575–579, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25800

In this paper, an improved maximum power point (MPP) tracking (MPPT) with better performance based on voltage-oriented control (VOC) is proposed to solve a fast-changing irradiation problem. In VOC, a cascaded control structure with an outer dc link voltage control loop and an inner current control loop is used. The currents are controlled in a synchronous orthogonal d,q frame using a decoupled feedback control. The reference current of proportional-integral (PI) d-axis controller is extracted from the dc-side voltage regulator by applying the energy-balancing control. Furthermore, in order to achieve a unity power factor, the q-axis reference is set to zero. The MPPT controller is applied to the reference of the outer loop control dc voltage photovoltaic (PV). Without PV array power measurement, the proposed MPPT identifies the correct direction of the MPP by processing the d-axis current reflecting the power grid side and the signal error of the PI outer loop designed to only represent the change in power due to the changing atmospheric conditions. The robust tracking capability under rapidly increasing and decreasing irradiance is verified experimentally with a PV array emulator. Simulations and experimental results demonstrate that the proposed method provides effective, fast, and perfect tracking.

For identifying a continuous-time (CT) transfer function model, data filtering is a solution which provides the necessary unmeasurable input--output derivative approximations. In discrete-time (DT) system identification, the well-known ARX model can be used successfully if the estimate is performed with suitable prefiltered data. This article describes the reinitialised partial moment (RPM) model which embeds implicitly a finite impulse response filter in both CT and DT domains. With knowledge of the important role of data prefiltering in standard methods, this RPM model embedded filter gives particular properties to this original tool. Although both the CT RPM model and the DT RPM model present an embedded filter, the formulation and the implementation in the CT and the DT domains are different. Therefore, the aim of this article is to present a tutorial on the RPM models and to give an overview of all the applications.

A haptic system is an articulated mechanical structure with motors, sensors, embedded electronics as well computer software allowing force feedback. It enables the user to interact with virtual reality through the sense of touch and sight. It has two main operating modes. In the blocked mode the haptic system should be able to reproduce virtual shocks [1][2]. In the transparent mode, the haptic system should be as transparent as possible. The transparency is defined as the quality of the free movement while displacing outside the blocked regions. A Permanent Magnet Synchronous Motor (PMSM) is used to drive the mechanical structure. Nowadays PMSM connectors use ultra-powerful magnet in order to reduce the motor volume with respect to the delivered electromagnetic torque ratio. Furthermore the use of those magnets, torque ripples phenomena (cogging torque) can be observed and it can deteriorate the haptic interface performances. In this paper a torque ripples identification and compensation method is proposed and evaluated experimentally. The developed least square identification procedure uses the measured currents, while the PMSM is driven at constant speed, in order to reconstruct the cogging signal. The main advantage of the proposed method is that it doesn't use the motor mechanical structure characteristics in order to calculate its parameters.

International audience; This paper presents a modeling and identification procedure for Radio Frequency Power Amplifier (PA) in continuous time representation. The proposed method is based on a combined approach using time and frequency domain. The microwave PA dynamics are described by the continuous Hammerstein model. The distortion function coefficients were estimated using Least Mean Squares (LMS) method that minimizes the squared error based on baseband output data. The coefficients of dynamic block are extracted using an iterative instrumental variable applied to experimental PA frequency responses. To demonstrate the feasibility of the identification method in experimental results we used a standard mobile PA at 1.85GHz.

A haptic system is an articulated mechanical structure with motors, sensors, embedded electronics as well computer software allowing force feedback. It enables the user to interact with virtual reality through the sense of touch and sight. The control of such systems can become unstable at low speed because of mediocre speed estimation quality. This paper describes the influence of diminution of the position encoder resolution on the estimated speed, since the speed is calculated using the position information. Further more, this paper illustrates the implementation of various speed estimation techniques, such as a full order state speed observer, Kalman filter and the synchronous constant elapsed time method (direct digital position derivation) for a single degree of freedom haptic interface driven by a permanent magnet synchronous motor. In addition, their influence on system stiffness is illustrated.

National audience

This paper presents a vision based Cart-Inverted Pendulum (CIP) system under a hybrid feedback configuration: the continuous cart’s position measured by encoder and the delayed & sampled inverted pendulum’s upper coordinates, obtained from a visual sensor. The challenge here is to stabilize the CIP from a big inclined initial angle by using a low cost CCD camera. Under this scheme, we propose a hybrid control which consists in a Jumpingup (Bang-Bang) control and a two causal stabilization loops control: the first one (inner loop) realizes a linearization and the stabilization control of the pendulum based on an innovative Piecewise Continuous Reduced Order Luenberger Observer coupled with a linearization module, the second one (the outer loop) realizes a Lyapunov based control for the unstable internal system with lower dynamics than that of the pendulum. This hybrid control method is capable of balancing the CIP system within small cart’s displacement. Performances issues of the proposed method are illustrated by the experimental figures and videos.

International audience; The type of control system used for electrical machines depends on the use (nature of the load, operating states, etc.) to which the machine will be put. The precise type of use determines the control laws which apply. Mechanics are also very important because they affect performance. Another factor of essential importance in industrial applications is operating safety. Finally, the problem of how to control a number of different machines, whose interactions and outputs must be coordinated, is addressed and solutions are presented. These and other issues are addressed here by a range of expert contributors, each of whom are specialists in their particular field. This book is primarily aimed at those involved in complex systems design, but engineers in a range of related fields such as electrical engineering, instrumentation and control, and industrial engineering, will also find this a useful source of information.

International audience; The type of control system used for electrical machines depends on the use (nature of the load, operating states, etc.) to which the machine will be put. The precise type of use determines the control laws which apply. Mechanics are also very important because they affect performance. Another factor of essential importance in industrial applications is operating safety. Finally, the problem of how to control a number of different machines, whose interactions and outputs must be coordinated, is addressed and solutions are presented. These and other issues are addressed here by a range of expert contributors, each of whom are specialists in their particular field. This book is primarily aimed at those involved in complex systems design, but engineers in a range of related fields such as electrical engineering, instrumentation and control, and industrial engineering, will also find this a useful source of information.

International audience

International audience

This paper presents a new control method entitled direct power control (DPC) for shunt active power filter (APF), which is applied to eliminate line current harmonics and compensate reactive power. Its main goal is to rebuild active and reactive source powers to be compared to references values using hysteresis control. The active power reference is issue of DC-side of inverter and reactive power reference is set to zero for unity power factor. The outputs of hysteresis controllers associated with a switching table, control the instantaneous active and reactive power by selecting the optimum switching state of the voltage source inverter (VSI). A theoretical analysis with a complete simulation of the system and experimental results are presented to prove the excellent performance of the proposed technique.

The present study addresses the initialisation problem of output-error (OE) identification methods. The challenge is to find a suitable initialization, which brings about a convergence towards the global optimum. A common way to initialise OE methods is to use the ARX model, but it must be used cautiously. The purpose of this study is to describe an alternative method based on the reinitialised partial moment (the RPM model) and to compare this approach with the ARX model by analysing the bias. The RPM model property is an implicit embedded filter that substitutes the explicit data filter required by the ARX model.

This paper analyses the synchronous machine modeling by taken into account the machine parameters usually used in industry and those used in researcher’s domains. Two models are presented. The first one is developed in the (d, q) natural reference frames and the other one is referred to the (d, q) stator reference frame. To do this, two methods are proposed to compute the reduction factor of the field winding without any input from design information. It is shown that the reduction factors of the (d, q) damper windings do not influence on the terminal behavior of the machine. This means that it is possible to know the terminal behavior of the machine without knowing the real inductances and resistances of the damper windings. The accuracy of these models is validated by experimental tests.

The doubly fed induction generator (DFIG) is generally used in the production of the electric energy and more specifically in wind turbines. Currently, a problem of electrical machine control and especially for wind turbines is the change of internal parameters of the machine, which greatly deteriorates the control. In addition, for stand-alone applications, the load and wind speed change frequently. In this paper, a robust control strategy based on the H ∞ control theory is developed for the independent control of the stator voltage amplitude and frequency of a stand-alone DFIG. The DFIG is fed through the rotor windings by a voltage inverter controlled by Space Vector Modulation (SVM). A capacitive and inductive filter is introduced to reduce harmonics on stator voltages and rotor currents. The robust control strategy rejects all the disturbances that may affect the system and that result from the variations of machine parameters, of the rotor speed and of the load. Experimental tests are carried out to verify the effectiveness of the robust control through a comparison with the classical PI regulator in the framework of the Field Oriented Control (FOC) strategy of the DFIG.

This paper is concerned with the design and implementation of current control of three-phase PWM rectifier based on predictive control strategy. The proposed predictive current control technique operates with constant switching frequency, using space-vector modulation (SVM). The main goal of the designed current control scheme is to maintain the dc-bus voltage at the required level and to achieve the unity power factor (UPF) operation of the converter. For this purpose, two predictive current control algorithms, in the sense of deadbeat control, are developed for direct controlling input current vector of the converter in the stationary α – β and rotating d – q reference frame, respectively. For both predictive current control algorithms, at the beginning of each switching period, the required rectifier average voltage vector allowing the cancellation of both tracking errors of current vector components at the end of the switching period, is computed and applied during a predefined switching period by means of SVM. The main advantages of the proposed predictive current control are that no need to use hysteresis comparators or PI controllers in current control loops, and constant switching frequency. Finally, the developed predictive current control algorithms were tested both in simulations and experimentally, and illustrative results are presented here. Results have proven excellent performance in steady and transient states, and verify the validity of the proposed predictive current control which is compared to other control strategies.

In this paper, we describe an original method for determining the optimal operating point of the active part (transistor ) of an LC oscillator leading to the minimum phase noise for given specifications in terms of power consumption, oscillation frequency and for given devices (i.e., transis tor and resonator). The key point of the proposed method is based on the use of a proper LC oscillator architecture providing a fixed loaded quality fa ctor for different operating points of the active part within the oscillator. The feedbac k network of this architecture is made of an LC resonator with coupling transformers. In these conditions, we show that it is possible to easily change the operating point of the amplifier, through the determination of the turns ratio o f those transformers, and observe its effect on phase noise without modifying the loaded quality factor of the resonator. The optimal operating point for minimum phase noise is then extracted from nonlinear simulations. Once this optimal behaviour of the active part known and by associating the previous LC resonator, a design of an LC oscillator or VCO with an optimal phase noise becomes possible. The conclusions of the presented simulation results have been widely used to design and implement a fully integrated, LC differential VCO on a 0.35 μm BiCMOS SiGe process. Mobile communication system evolution demands continuous efforts toward the improvement of RadioFrequency (RF) circuit performances. Concerning the oscillators and voltage-controlled oscillators (VCOs), the phase noise requirements are even more stringent. Indeed, the carrier rejection and the transmission quality of any systems depend on the phase noise of the signals applied to the modulator. Furthermore, from the designer point of view, pressure is growing as design time is getting shorter and shorter. In this context, it seems to be very interesting to know rapidly if the specification required in terms of phase noise and consumption are consistent with the technology provided. Due to these considerations, this paper describes a method for determining the optimal operating point of the active part of an LC oscillator leading to the minimum phase noise for given specifications in terms of power consumption, oscillation frequency and for given devices.

International audience; This paper presents, in a first time, an original method of smart antenna design, based on an antenna array driven by vector modulators. Different radiation patterns are measured to validate the method. In a second time, we show the interest in using such antenna array in transports domain. Thus, we first integrate these radiation patterns into a 3D propagation simulator based on Ray-Tracing, to achieve deterministic simulations of wave propagation in site specific environment (dense urban, urban, suburban). Then, we perform some simulations of an OFDM communication on a mobility scenario in a realistic urban environment taking into account antennas and channel behavior. Significant gains in terms of power consumption, electromagnetic de-pollution and Bit Error Rate (BER) are provided with smart antennas in comparison with dipole antenna.

International audience; In this paper, a method to study and characterize a single-loop, cascaded and 1-bit band-pass delta sigma (BPΔΣ) modulator for digital transmitter is presented. This technique is based on a combination of digital filter simulation and nonlinear optimization of signal-to-quantization noise. The optimal coefficients of BPΔΣ structure are achieved by minimization of a quadratic criterion based on prediction error between desired digital filter and noise transfer model. To demonstrate the effectiveness of this approach, simulated results for a 6th order cascaded structure for WCDMA band-1 standard are presented.

International audience; This article presents a new Low-Pass Delta Sigma Modulators (LPDS) architecture to improve the noise shaping for high frequency applications. The errors resulting from approximations made by calculating with 1/2N coefficients are compensated. Simulations with extracted parasitics of the layout are made and give a SNDR of 111 dB, 3.8 mW power consumption at 4 GHz in 65 nm CMOS technology for UMTS standard.

International audience

International audience; This paper deals with the synchronization of a chain of nonlinear and uncertain models of nonidentical oscillators. Using Lyapunov's theory of stability, a dynamical controller guaranteeing the synchronization of the oscillators is determined. The problem of synchronization is transformed into a problem of asymptotic stabilization for a nonlinear system and then is formulated as a system of linear matrix inequalities where the parameter variations of the two oscillators and their differences are modeled by polytopic matrices. The theoretical result is successfully applied to an array of transistor-based oscillators used in "smart antenna" systems.

A haptic system is an articulated mechanical structure with motors, sensors as well embedded electronics allowing force feedback. It enables the user to interact with virtual reality through the sense of touch and sight. Speed control of such systems usually becomes unstable at low speed range due to the imposed speed by the operator's hand. This paper describes implementation of full order state speed observer for a single degree of freedom haptic interface driven by permanent magnet synchronous motor. This method allows accurate speed estimation. The observer design criteria for haptic interface are analyzed in this paper. In addition, its influence on system stiffness is illustrated.

From the unicity and orthogonality properties of chaotic sequences, it is demonstrated that a sum of N chaotic signals generated from a fixed class of chaotic systems is unique. Consequently, within a framework of a multi-user transmission, it is shown that synchronizing N chaotic carriers that emit simultaneously on the same frequency band is feasible. In this paper, the carriers are generated from Chua’s circuits and are modulated in amplitude by the information signal. Demodulation is ensured by the minimization of a cost function. Numerical simulations show that this synchronization method is robust in presence of noise and allows the integration of a high number of users.

International audience; In this paper, a method to study and characterize a single-loop, cascaded and 1-bit Band-Pass Delta Sigma modulator for digital transmitter is presented. This technique is based on a combination of digital filter simulation and nonlinear optimization of signal-to-quantization noise. The optimal coefficients of modulator structure are achieved by minimization of a quadratic criterion based on prediction error between desired digital filter and noise transfer model. To demonstrate the effectiveness of this approach, simulated results for a sixth order cascaded structure for WCDMA Band-1 standard are presented. Spurious and ACLR improvement could be achieved for this standard with the proposed characterization technique.

National audience; En termes de pollution électromagnétique et de rapport Signal/Bruit, l'efficacité des transmissions radio peut être accrue par l'utilisation d'antennes intelligentes. Ce papier présente la conception et principalement l'intérêt d'utiliser des modulateurs vectoriels pour commander la formation de faisceaux avec un réseau d'antennes. Les diagrammes de rayonnement pour différents dépointages ont été mesurés et sont présentés. Ces différents diagrammes sont ensuite intégrés dans un outil de simulation de propagation d'onde radio (en 3D) afin de démontrer les bénéfices inhérents à une telle commande d'antenne dans le cadre d'un système de communication numérique, notamment en termes d'efficacité énergétique et de dépollution électromagnétique.

This paper presents a stabilization control system of a 3D inverted pendulum. The challenge is to realize a control via remote sensing based on a low cost CCD camera. The proposed method transforms the 3D problem into a 2D one by choosing a new balacing plane for the pendulum at each camera's sampling instant. For a given plane, two feedback loops are considered. The first one, which is an observation loop, processes the delayed and sampled angle information delivered by the artificial vision system so as to set up a linear and stable model of the pendulum (without any approximations) and to reconstitue its continuous state by means of a specific observer called Plecewise Continuous reduced-order Luenberger Observer (PCO). The second loop, which is a stabilitation loop , makes use of a Lyapunov function based control in order to stabilise the cart-pendulum system. Simulations and experimental results illustrate the method's performance.

A new approach on synchronous generator (SG) output voltage control is presented. The originality of such a strategy is based on the excitation structure that integrates a permanent-magnet generator combined with a modern control method: the H infin. The main motivation of this paper is the debatable results obtained with the classical excitation structure controlled by a traditional PID controller. The SG model as well as the control strategy will be presented. The implementation in real time domain and a comparison with the classical structure will allow us to prove the efficiency of the proposed structure compared to the classical one as regards the reference tracking and signal quality.

National audience; Dans cette communication, nous présentons l'application d'une technique de contre réaction pour la linéarisation des amplificateurs de puissance radio fréquence. Cette technique est basée sur le principe de la commande par modèle interne (CMI) qui utilise comme signal de commande l'écart entre les signaux en bande de base en sortie du système et de son modèle. Afin de valider cette méthode, des résultats de simulation sont présentés.

International audience; We consider the problem of identifying switched linear state space models from a finite set of input-output data. This is a challenging problem, which requires inferring both the discrete state and the parameter matrices associated with each discrete state. An important contribution of our work is that we do not make the restrictive assumption of minimum dwell time between the switches, as it is customary in methods that deal with such models. We first propose a technique for eliminating the unknown continuous state from the model equations under an appropriate assumption of observability. On a time horizon, this gives us a new switched input-output relation that involves structured intermediary matrices, which depend on the state space representation matrices. To estimate the intermediary matrices, we present a randomly initialized algorithm that alternates between data classification and parameter update via recursive least squares. Given these matrices, the parameters associated to the different discrete states can be computed after a correct estimation of the discrete state.

International audience; This paper is concerned with the identification of switched linear MIMO state-space systems in a recursive way. Firstly, a structured subspace identification scheme for linear systems is presented which turns out to have many attractive features. More precisely, it does not require any singular value decomposition (SVD) but is derived using orthogonal projection techniques; it allows a computationally appealing implementation and it is closely related to input-output models identification. Secondly, it is shown that this method can be implemented on-line to track both the range space of the extended observability matrix and its dimension and thereby, the system matrices. Thirdly, by making use of an on-line switching times detection strategy, this method is applied to blindly identify switched systems and to label the obtained submodels. Simulation results on noisy data illustrate the abilities and the benefits of the proposed approach.

This paper proposes direct power control (DPC) for three-phase PWM rectifiers using a new switching table, without line voltage sensors. The instantaneous active and reactive powers, directly controlled by selecting the optimum state of the converter, are used as the PWM control variables instead of the phase line currents being used. The main goal of the control system is to maintain the dc-bus voltage at the required level, while input currents drawn from the power supply should be sinusoidal and in phase with respective phase voltages to satisfy the unity power factor (UPF) operation. Conventional PI and a designed fuzzy logic-based controller, in the dc-bus voltage control loop, have been used to provide active power command. A dSPACE based experimental system was developed to verify the validity of the proposed DPC. The steady-state, and dynamic results illustrating the operation and performance of the proposed control scheme are presented. As a result, it was confirmed that the novel DPC is much better than the classical one. Line currents very close to sinusoidal waveforms (THD < 2%) and good regulation of dc-bus voltage are achieved using PI or fuzzy controller. Moreover, fuzzy logic controller gives excellent performance in transient state, a good rejection of impact load disturbance, and a good robustness.

International audience; During the past decade, coupled oscillators have shown their efficiency as simple methods for phase control in microwave antenna arrays, and hence as alternatives to conventional electronic beam steering methods. In this paper, a new writing of the nonlinear equations proposed by R. York to describe the oscillators' locked states is presented. This has allowed the elaboration of a CAD tool which provides, in a considerably short simulation time, the frequency locking region of the coupled oscillators. This region is plotted versus the oscillators' tunings referred to the resonant frequency of the coupling circuit. A prototype circuit consisting of a five oscillators array is currently under test to validate the theory.

Heat transfer in a homogeneous medium obeys diffusion phenomena, which can be modelled with the help of fractional systems. In this paper, we use fractional models based on an original fractional integrator whose order 1/2 acts only over a limited spectral band. These models, not linear in thermal parameters but linear in structural parameters, allow us to provide accurate simulations for transients with which it is possible to apply an output error technique to estimate the thermophysical parameters. Simulations of front face thermal characterization consisting of measuring the temperature at the surface of a material where a random heat flux is applied are carried out. These simulations allow us to validate the ability of the proposed estimation algorithms not only to rebuild the surface temperature but also to identify with a good accuracy the heat conductivity and diffusivity. Monte Carlo simulations are also performed in order to provide statistical properties of the thermal parameter estimates.

National audience; Dans les domaines des radiocommunications, le contrôle conjoint de l'orientation et de la formation des diagrammes de rayonnement augmente considérablement la qualité de la communication. En effet, des points clés tels que la répartition de la puissance émise et le rapport Signal/Bruit sont améliorés. Cette commande de l'orientation est réalisée en contrôlant la phase injectée sur chacun des éléments rayonnants qui constitue le réseau. Une des techniques consiste à coupler des oscillateurs entre eux, et ce papier présente la conception d'un prototype ainsi que les résultats expérimentaux qui valident un outil de CAO développé au sein de notre laboratoire.