Electrocardiogram (ECG) signals are often contaminated with artefacts and noises which can lead to incorrect diagnosis when they are visually inspected by cardiologists. In this paper, the well-known discrete Fourier series (DFS) is re-explored and an efficient DFS-based method is proposed to reduce contribution of both baseline wander (BW) and powerline interference (PLI) noises in ECG records. In the first step, the determination of the exact number of low frequency harmonics contributing in BW is achieved. Next, the baseline drift is estimated by the sum of all associated Fourier sinusoids components. Then, the baseline shift is discarded efficiently by a subtraction of its approximated version from the original biased ECG signal. Concerning the PLI, the subtraction of the contributing harmonics calculated in the same manner reduces efficiently such type of noise. In addition of visual quality results, the proposed algorithm shows superior performance in terms of higher signal-to-noise ratio and smaller mean square error when faced to the DCT-based algorithm.

High order modulation (HOM) presents a key challenge in increasing spectrum efficiency in 4G and upcoming 5G communication systems. In this paper, two non-linear adaptive equalizer techniques based on multilayer perceptron (MLP) and radial basis function (RBF) are designed and applied on HOM to optimize its performance despite its high sensitivity to noise and channel distortions. The artificial neural network’s (ANN) adaptive equalizer architectures and learning methods are simplified to avoid more complexity and to ensure greater speed in symbol decision making. They will be compared with the following popular adaptive filters: least mean square (LMS) and recursive least squares (RLS), in terms of bit error rate (BER) and minimum square error (MSE) with 16, 64, 128, 256, 512 and 1024 quadrature amplitude modulation (QAM). By that, this work will show the advantage that the MLP equalizer has, in most cases, over RBF and traditional linear equalizers. © 2018 National Institute of Telecommunications. All rights reserved.

L’Algérie possède un gisement solaire très important dû à sa grande superficie dont la majorité est aride ou semi-aride, contenant un nombre important de fermes agricoles qui peuvent être divisées en deux types : le premier est connecté au réseau conventionnel tandis que le second est situé dans des zones isolées. Ces deux types de fermes souffrent de nombreux problèmes dus au manque d'électrification ou de son insuffisance durant les périodes estivales. Dans cette étude, nous nous intéressons aux fermes des sites isolés; elles utilisent pour l’alimentation électrique des moteurs diesel qui sont limités principalement à l'irrigation et à l'éclairage des maisons pendant quelques heures par jour en raison des coûts élevés du carburant et de l'entretien des moteurs. Comme l'Algérie est l'un des pays qui a des journées ensoleillées durant toute l'année, l'énergie solaire peut contribuer à résoudre ce type de problèmes en alimentant les fermes en électricité et en leur apportant certains avantages. Dans cette étude, nous faisons l’étude d’une ferme typique dans un site isolé, tout en montrant comment l’énergie solaire peut contribuer à son alimentation en énergie électrique amicale à l’environnement.

In this work, a new ultraviolet optically-controlled field-effect transistor (UV-OCFET) based on ZnMgO photosensitive gate with graded band-gap aspect is proposed and investigated using a comprehensive analytical modeling. The impact of different band-gap profiles on the phototransistor figure of merits (FoMs) is analyzed. Our study demonstrates that the use of ZnMgO with a graded band-gap profile can generate an electric field in the photosensitive layer, which leads to achieve the dual role of effective electron/hole pair separation and lower recombination losses. Moreover, increasing the Mg content progressively not only enables a strong UV-light absorption but also allows achieving a high optical sensitivity for very low optical powers (sub-1pW). The particle-swarm optimization approach is exploited to boost the phototransistor FoMs by optimizing the sensor design parameters and the ZnMgO band-gap profile. It is found that the optimized structure exhibits superior optical characteristics as compared to those of the conventional UV-photodetectors. Therefore, the optimized ZnMgO UV-OCFET with graded band-gap paradigm pinpoints a new path toward recording an ultrasensitive phototransistor compatible with CMOS modern technology. This makes it a potential alternative for high-performance and low-energy consumption chip-level UV-communication and monitoring applications.