Alexandre Mallet

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This paper presents a method for the optimization of the power-added efficiency (PAE), as well as the error-vector measurement (EVM) of a 20-GHz power amplifier (PA) applied in this case to the M quadrature and amplitude modulations. A first key point lies in that both input and output biasing voltages of the solid-state power amplifiers (SSPAs) are(More)
Images may contain blemishes or artificial structures which come from the processing or directly from the sensors, that decrease the quality of the images and can lead to analysis and interpretation problems. We are interested in detecting these defects automatically. The aim of our method will be to look for artifacts as too regular or too irregular image(More)
In this paper, we are interested in estimating parameters entering nonlinear mixed effects models using a likelihood maximization approach. As the accuracy of the likelihood approximation is likely to govern the quality of the derived estimates of both the distribution of the random effects and the fixed parameters, we propose a methodological approach(More)
This paper discusses the suitability of using a multiport amplifier (MPA) for a power section of space telecommunication payloads with power flexibility requirements. The performances of an MPA-based architecture are compared to those of a classical amplification architecture having one power amplifier per beam. This study is based on a 4 times 4 Ka-band(More)
— This paper presents a novel and non quasi static behavioral (black box) model of power amplifiers. It takes into account nonlinear memory effects for an accurate prediction of signal distortions and power budget in communication systems. The model topology and the model extraction procedure are described. The model proposed in this paper can be derived(More)
Model-order reduction techniques of RF and microwave linear and weakly nonlinear time-varying circuits are presented. The reduced models capture the memory and linear or weakly nonlinear input-output behavior of the circuit, as well as the matching conditions at the model ports. The reported techniques serve to reduce models of a number of RF and microwave(More)
An automatic image pattern analysis method based on differential densitometry is presented. It is applied to histological sections of mouse cerebellum. This method allows an automatic recognition of any cerebellar microscopic field. After recognition, histological images are decomposed into homogeneous parts with respect to cerebellar cellular layers, and(More)