Revue Méditerranéenne des Télécommunications, Apr 20, 2012
Au cours des dernieres annees, on assiste a une expansion de la transmission multimedia via la te... more Au cours des dernieres annees, on assiste a une expansion de la transmission multimedia via la technologie courants porteurs en lignes (CPL). La plupart des travaux sur CPL ont opte pour la modulation multi-porteuse OFDM (Orthogonal Frequency Division Multiplexing) comme technique de transmission. Mais cette modulation, basee sur une mise en forme spectrale rectangulaire, possede des inconvenients notables comme une densite spectrale de puissance ayant des lobes secondaires tres eleves. D'autres modulations ont ete developpees pour lutter contre ce probleme. Nous proposons dans ce papier l’etude de la modulation OFDM surechantillonnee sur plusieurs aspects critiques, afin de l’adapter a la transmission d’information via un canal CPL. Notre contribution sera focalisee sur l'etude de la densite spectrale de puissance (DSP) du signal OFDM surechantillonne, afin d’optimiser une chaine de transmission numerique haut debit sur les canaux CPL indoor. Cette methode consiste a adapter les parametres de modulation pour diminuer les pertes d’information. Pour cela nous allons examiner trois schemas de modulations OFDM, pour montrer l’efficacite de la methode proposee.
This paper suggests the analysis and the simulation of a thermoelectric heat pump for heating a s... more This paper suggests the analysis and the simulation of a thermoelectric heat pump for heating a small-size office building in Ifrane (Morocco). Meteorological data of the site are imported from the METEONORM Database and used by the TRNSYS building's simulator in order to estimate the heating loads of the office building. The thermoelectric heat pump coupled to the building was mathematically modeled and the set of equations were solved in MATLAB to evaluate the system's performance. The number of modules maximizing the coefficient of performance and the optimal electric current were determined for extreme operating conditions.
This paper is an energy audit performed for an industrial site based in FEZ (Morocco), specialize... more This paper is an energy audit performed for an industrial site based in FEZ (Morocco), specialized in producing and commercializing cattle feed It evaluates the economic gains related to an optimized management of the electrical energy use and focuses on the improvement of energy efficiency for the interior lighting.
2017 International Conference on Wireless Technologies, Embedded and Intelligent Systems (WITS)
This paper presents the design of an imaging FMCW (Frequency-Modulated Continuous-Wave) radar sys... more This paper presents the design of an imaging FMCW (Frequency-Modulated Continuous-Wave) radar system operating in the frequency band 75–110 GHz. The 35-GHz bandwidth offers a theoretical longitudinal resolution of 4.2 mm to detect inner defects. The study concerns defects such as holes and cracks. True 3D imaging is obtained by scanning transversally the material under test, the transverse resolution being limited by the beam waist.
Presently, great challenges are being faced by the industrial sector in terms of energy managemen... more Presently, great challenges are being faced by the industrial sector in terms of energy management and environmental protection. Utilization of solar energy to meet a portion of heat demand in various industries constitutes tremendous economic opportunities for developing countries such as Morocco. Therefore, this paper introduces an optimization procedure and simulation of a centralized solar heating system providing hot water to four processes with different temperature levels and load profiles. Asa case study, a Casablanca based Moroccan milk processing company is evaluated and the life cycle cost method is practiced to select the optimal size of the main design parameters for decision-making. It was found that 400m2 of evacuated tube collectors tilted at an angle of 30° and connected to a 2000l storage tank can lead to a maximum life cycle saving cost of 179kUSD for a total annual heat demand of 528.23MWh. In this optimal configuration, the overall annual solar fraction is found to be 41% and the payback period of 12.27years attained. The system has the potential to reduce around 77.23tons of CO2 equivalents of greenhouse gas emissions annually. The economic competitiveness of the solar thermal heating plant can be considerably improved with higher inflation rates and lower initial investments.
In the RFID sensor network (RSN), the devices communicate with each other by RF waves using the a... more In the RFID sensor network (RSN), the devices communicate with each other by RF waves using the antennas through a propagation channel. A poor communication between these devices results in either a significant economic loss or security threats. The communication problems can have several origins depending on the type of antenna used and the nature of the propagation channel. In this work, our objective is to limit the communication problems between the nodes of this network that are linked to the characteristics of an indoor propagation channel. The goal is to predict the channel characteristics using the 3D ray tracing method in order to select the appropriate transmission parameters such as transmission power and duration of a symbol. To achieve this, we have modeled a building that is sectioned as a propagation channel where network devices are deployed for control and monitoring. The communication was made at 915 MHz using the quasi-isotropic 3D cubic antenna that we designed a...
The International Journal on Communications Antenna and Propagation, 2013
Power Line Communications have been the subject of an important research work. At the same time, ... more Power Line Communications have been the subject of an important research work. At the same time, the growing demand for multimedia communications provides a good prospect for PLC as a promising transmission technique for the “last mile” access network. Orthogonal Frequency Division Multiplexing (OFDM) is a spectrally efficient multicarrier modulation technique for high speed data transmission over multipath fading channels. High Peak-to-Average Power Ratio (PAPR) is a major drawback of OFDM. The high PAR of the OFDM signal has to be considered when setting the range of the digital-to-analog converter (DAC) and dimensioning the line-driver. This paper introduced an improved PAPR reduction scheme using constant envelope modulation. Furthermore, by utilizing continuous phase modulation (CPM) in a CE-OFDM system, the PAPR can be effectively reduced to 0 dB. The paper describes a CE-OFDM based modem for Power Line Communications (PLC) over the low voltage distribution network. Relying on...
2017 International Symposium on Electromagnetic Compatibility - EMC EUROPE, 2017
Undesired EM radiation generated by wired systems using a PLC transmission, for example, can be a... more Undesired EM radiation generated by wired systems using a PLC transmission, for example, can be a source of EM pollution and bring an annoying problem of electromagnetic compatibility. The evaluation of these near-field radiation is therefore of interest. In this paper, we propose a simplified approach of electromagnetic fields in order to adequately estimate the EM radiation emitted by the wired systems with a simple measurement of currents and its first two derivatives at discontinuities (geometric and electric). This model is capable of handling cases where the identification of the current along the lines network is complicated and numerically consuming (FEKO, NEC, etc.). The validation consists of processing the case of a two-wire line of finite conductivity, and we have studied the influence of the distance between the conductive wires of this line on the electromagnetic radiation impact.
Revue Méditerranéenne des Télécommunications, Apr 20, 2012
Au cours des dernieres annees, on assiste a une expansion de la transmission multimedia via la te... more Au cours des dernieres annees, on assiste a une expansion de la transmission multimedia via la technologie courants porteurs en lignes (CPL). La plupart des travaux sur CPL ont opte pour la modulation multi-porteuse OFDM (Orthogonal Frequency Division Multiplexing) comme technique de transmission. Mais cette modulation, basee sur une mise en forme spectrale rectangulaire, possede des inconvenients notables comme une densite spectrale de puissance ayant des lobes secondaires tres eleves. D'autres modulations ont ete developpees pour lutter contre ce probleme. Nous proposons dans ce papier l’etude de la modulation OFDM surechantillonnee sur plusieurs aspects critiques, afin de l’adapter a la transmission d’information via un canal CPL. Notre contribution sera focalisee sur l'etude de la densite spectrale de puissance (DSP) du signal OFDM surechantillonne, afin d’optimiser une chaine de transmission numerique haut debit sur les canaux CPL indoor. Cette methode consiste a adapter les parametres de modulation pour diminuer les pertes d’information. Pour cela nous allons examiner trois schemas de modulations OFDM, pour montrer l’efficacite de la methode proposee.
This paper suggests the analysis and the simulation of a thermoelectric heat pump for heating a s... more This paper suggests the analysis and the simulation of a thermoelectric heat pump for heating a small-size office building in Ifrane (Morocco). Meteorological data of the site are imported from the METEONORM Database and used by the TRNSYS building's simulator in order to estimate the heating loads of the office building. The thermoelectric heat pump coupled to the building was mathematically modeled and the set of equations were solved in MATLAB to evaluate the system's performance. The number of modules maximizing the coefficient of performance and the optimal electric current were determined for extreme operating conditions.
This paper is an energy audit performed for an industrial site based in FEZ (Morocco), specialize... more This paper is an energy audit performed for an industrial site based in FEZ (Morocco), specialized in producing and commercializing cattle feed It evaluates the economic gains related to an optimized management of the electrical energy use and focuses on the improvement of energy efficiency for the interior lighting.
2017 International Conference on Wireless Technologies, Embedded and Intelligent Systems (WITS)
This paper presents the design of an imaging FMCW (Frequency-Modulated Continuous-Wave) radar sys... more This paper presents the design of an imaging FMCW (Frequency-Modulated Continuous-Wave) radar system operating in the frequency band 75–110 GHz. The 35-GHz bandwidth offers a theoretical longitudinal resolution of 4.2 mm to detect inner defects. The study concerns defects such as holes and cracks. True 3D imaging is obtained by scanning transversally the material under test, the transverse resolution being limited by the beam waist.
Presently, great challenges are being faced by the industrial sector in terms of energy managemen... more Presently, great challenges are being faced by the industrial sector in terms of energy management and environmental protection. Utilization of solar energy to meet a portion of heat demand in various industries constitutes tremendous economic opportunities for developing countries such as Morocco. Therefore, this paper introduces an optimization procedure and simulation of a centralized solar heating system providing hot water to four processes with different temperature levels and load profiles. Asa case study, a Casablanca based Moroccan milk processing company is evaluated and the life cycle cost method is practiced to select the optimal size of the main design parameters for decision-making. It was found that 400m2 of evacuated tube collectors tilted at an angle of 30° and connected to a 2000l storage tank can lead to a maximum life cycle saving cost of 179kUSD for a total annual heat demand of 528.23MWh. In this optimal configuration, the overall annual solar fraction is found to be 41% and the payback period of 12.27years attained. The system has the potential to reduce around 77.23tons of CO2 equivalents of greenhouse gas emissions annually. The economic competitiveness of the solar thermal heating plant can be considerably improved with higher inflation rates and lower initial investments.
In the RFID sensor network (RSN), the devices communicate with each other by RF waves using the a... more In the RFID sensor network (RSN), the devices communicate with each other by RF waves using the antennas through a propagation channel. A poor communication between these devices results in either a significant economic loss or security threats. The communication problems can have several origins depending on the type of antenna used and the nature of the propagation channel. In this work, our objective is to limit the communication problems between the nodes of this network that are linked to the characteristics of an indoor propagation channel. The goal is to predict the channel characteristics using the 3D ray tracing method in order to select the appropriate transmission parameters such as transmission power and duration of a symbol. To achieve this, we have modeled a building that is sectioned as a propagation channel where network devices are deployed for control and monitoring. The communication was made at 915 MHz using the quasi-isotropic 3D cubic antenna that we designed a...
The International Journal on Communications Antenna and Propagation, 2013
Power Line Communications have been the subject of an important research work. At the same time, ... more Power Line Communications have been the subject of an important research work. At the same time, the growing demand for multimedia communications provides a good prospect for PLC as a promising transmission technique for the “last mile” access network. Orthogonal Frequency Division Multiplexing (OFDM) is a spectrally efficient multicarrier modulation technique for high speed data transmission over multipath fading channels. High Peak-to-Average Power Ratio (PAPR) is a major drawback of OFDM. The high PAR of the OFDM signal has to be considered when setting the range of the digital-to-analog converter (DAC) and dimensioning the line-driver. This paper introduced an improved PAPR reduction scheme using constant envelope modulation. Furthermore, by utilizing continuous phase modulation (CPM) in a CE-OFDM system, the PAPR can be effectively reduced to 0 dB. The paper describes a CE-OFDM based modem for Power Line Communications (PLC) over the low voltage distribution network. Relying on...
2017 International Symposium on Electromagnetic Compatibility - EMC EUROPE, 2017
Undesired EM radiation generated by wired systems using a PLC transmission, for example, can be a... more Undesired EM radiation generated by wired systems using a PLC transmission, for example, can be a source of EM pollution and bring an annoying problem of electromagnetic compatibility. The evaluation of these near-field radiation is therefore of interest. In this paper, we propose a simplified approach of electromagnetic fields in order to adequately estimate the EM radiation emitted by the wired systems with a simple measurement of currents and its first two derivatives at discontinuities (geometric and electric). This model is capable of handling cases where the identification of the current along the lines network is complicated and numerically consuming (FEKO, NEC, etc.). The validation consists of processing the case of a two-wire line of finite conductivity, and we have studied the influence of the distance between the conductive wires of this line on the electromagnetic radiation impact.
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