The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
M.a. Bouchene - One of the best experts on this subject based on the ideXlab platform.
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Role of the Radiated Field in the propagation of an ultra-short chirped pulse
Optics Communications, 2003Co-Authors: J.c. Delagnes, V. Blanchet, M.a. BoucheneAbstract:An ultrashort chirped pulse propagating in an optically dense atomic medium may undergo strong modulation on time scale shorter than its duration. We report in this paper a theoretical and experimental study of these reshaping effects. We demonstrate that two kinds of interferences are involved. The first one is due to the interference between the electric Field Radiated at resonance and that Radiated off resonance, inducing thus a modulation in the time profile of both the Radiated Field and the excited state population. The second one results from the interference between the Radiated Field and the incident one. Moreover, we show that after a transient time of the order of 2rootdelta(-1) where delta is the chirp parameter, the reshaping effects observed on the output intensity result from only the interference between the resonant part of the Radiated Field and the incident pulse. (C) 2003 Elsevier B.V. All rights reserved.
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Role of the Radiated Field in the propagation of an ultra-short chirped pulse
Optics Communications, 2003Co-Authors: J.c. Delagnes, V. Blanchet, M.a. BoucheneAbstract:Abstract An ultrashort chirped pulse propagating in an optically dense atomic medium may undergo strong modulation on time scale shorter than its duration. We report in this paper a theoretical and experimental study of these reshaping effects. We demonstrate that two kinds of interferences are involved. The first one is due to the interference between the electric Field Radiated at resonance and that Radiated off resonance, inducing thus a modulation in the time profile of both the Radiated Field and the excited state population. The second one results from the interference between the Radiated Field and the incident one. Moreover, we show that after a transient time of the order of 2 δ −1 where δ is the chirp parameter, the reshaping effects observed on the output intensity result from only the interference between the resonant part of the Radiated Field and the incident pulse.
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Role of the Radiated Field in the propagation of an ultra-short chirped pulse
Optics Communications, 2003Co-Authors: J.c. Delagnes, V. Blanchet, M.a. BoucheneAbstract:International audienceAn ultrashort chirped pulse propagating in an optically dense atomic medium may undergo strong modulation on time scale shorter than its duration. We report in this paper a theoretical and experimental study of these reshaping effects. We demonstrate that two kinds of interferences are involved. The first one is due to the interference between the electric Field Radiated at resonance and that Radiated off resonance, inducing thus a modulation in the time profile of both the Radiated Field and the excited state population. The second one results from the interference between the Radiated Field and the incident one. Moreover, we show that after a transient time of the order of 2rootdelta(-1) where delta is the chirp parameter, the reshaping effects observed on the output intensity result from only the interference between the resonant part of the Radiated Field and the incident pulse. (C) 2003 Elsevier B.V. All rights reserved
Fei Yang - One of the best experts on this subject based on the ideXlab platform.
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Radiated Field of rotating charged parallel plates and its frequency spectrum
AIP Advances, 2018Co-Authors: Zongxin Wang, Fei YangAbstract:Antennas in the ultra low frequency (ULF, 300 Hz to 3 kHz) and very low frequency (VLF, 3∼30 kHz) bands are usually very large. In this study, we developed a very small antenna, which can radiate electromagnetic waves in these frequency bands. The antenna consisted of two rotating charged plates (RCPs), which were charged by the voltage source. Numerical results of the Radiated far Field and its frequency spectrum are presented for three cases: (a) the antenna is charged with DC voltage, (b) the antenna is charged with AC voltage, and (c) the antenna rotates with variable speed and is fed with DC voltage. The predominant frequency component was equal to the rotating frequency of the RCPs fed with DC voltage. If the RCPs were fed with AC voltage two dominant frequencies were generated, which were determined by the difference in frequency between the RCP rotation frequency and the AC source frequency. When the RCPs rotated with variable speed and were fed with DC voltage, many frequency components were gene...
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Radiated Field of rotating charged parallel plates and its frequency spectrum
AIP Publishing LLC, 2018Co-Authors: Zongxin Wang, Zhenxin Cao, Fei YangAbstract:Antennas in the ultra low frequency (ULF, 300 Hz to 3 kHz) and very low frequency (VLF, 3∼30 kHz) bands are usually very large. In this study, we developed a very small antenna, which can radiate electromagnetic waves in these frequency bands. The antenna consisted of two rotating charged plates (RCPs), which were charged by the voltage source. Numerical results of the Radiated far Field and its frequency spectrum are presented for three cases: (a) the antenna is charged with DC voltage, (b) the antenna is charged with AC voltage, and (c) the antenna rotates with variable speed and is fed with DC voltage. The predominant frequency component was equal to the rotating frequency of the RCPs fed with DC voltage. If the RCPs were fed with AC voltage two dominant frequencies were generated, which were determined by the difference in frequency between the RCP rotation frequency and the AC source frequency. When the RCPs rotated with variable speed and were fed with DC voltage, many frequency components were generated, which were determined by the initial rotational speed of the RCPs and their acceleration
J.c. Delagnes - One of the best experts on this subject based on the ideXlab platform.
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Role of the Radiated Field in the propagation of an ultra-short chirped pulse
Optics Communications, 2003Co-Authors: J.c. Delagnes, V. Blanchet, M.a. BoucheneAbstract:An ultrashort chirped pulse propagating in an optically dense atomic medium may undergo strong modulation on time scale shorter than its duration. We report in this paper a theoretical and experimental study of these reshaping effects. We demonstrate that two kinds of interferences are involved. The first one is due to the interference between the electric Field Radiated at resonance and that Radiated off resonance, inducing thus a modulation in the time profile of both the Radiated Field and the excited state population. The second one results from the interference between the Radiated Field and the incident one. Moreover, we show that after a transient time of the order of 2rootdelta(-1) where delta is the chirp parameter, the reshaping effects observed on the output intensity result from only the interference between the resonant part of the Radiated Field and the incident pulse. (C) 2003 Elsevier B.V. All rights reserved.
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Role of the Radiated Field in the propagation of an ultra-short chirped pulse
Optics Communications, 2003Co-Authors: J.c. Delagnes, V. Blanchet, M.a. BoucheneAbstract:Abstract An ultrashort chirped pulse propagating in an optically dense atomic medium may undergo strong modulation on time scale shorter than its duration. We report in this paper a theoretical and experimental study of these reshaping effects. We demonstrate that two kinds of interferences are involved. The first one is due to the interference between the electric Field Radiated at resonance and that Radiated off resonance, inducing thus a modulation in the time profile of both the Radiated Field and the excited state population. The second one results from the interference between the Radiated Field and the incident one. Moreover, we show that after a transient time of the order of 2 δ −1 where δ is the chirp parameter, the reshaping effects observed on the output intensity result from only the interference between the resonant part of the Radiated Field and the incident pulse.
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Role of the Radiated Field in the propagation of an ultra-short chirped pulse
Optics Communications, 2003Co-Authors: J.c. Delagnes, V. Blanchet, M.a. BoucheneAbstract:International audienceAn ultrashort chirped pulse propagating in an optically dense atomic medium may undergo strong modulation on time scale shorter than its duration. We report in this paper a theoretical and experimental study of these reshaping effects. We demonstrate that two kinds of interferences are involved. The first one is due to the interference between the electric Field Radiated at resonance and that Radiated off resonance, inducing thus a modulation in the time profile of both the Radiated Field and the excited state population. The second one results from the interference between the Radiated Field and the incident one. Moreover, we show that after a transient time of the order of 2rootdelta(-1) where delta is the chirp parameter, the reshaping effects observed on the output intensity result from only the interference between the resonant part of the Radiated Field and the incident pulse. (C) 2003 Elsevier B.V. All rights reserved
Tan Phu Vuong - One of the best experts on this subject based on the ideXlab platform.
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Investigation on antenna's miniaturization using spherical wave expansion
2013Co-Authors: Kawtar Belmkaddem, Lionel Rudant, Tan Phu VuongAbstract:Spherical wave expansion is usually associated to electrically large antenna's measurements by transforming near Field to far Field and extracting its radiation properties. It has also been used in numerous investigations involving physical limitations of electrically small antennas. In this paper, spherical wave expansion is used as an engineering tool to analyze the impact of antenna miniaturization over the Radiated Field.
Zongxin Wang - One of the best experts on this subject based on the ideXlab platform.
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Radiated Field of rotating charged parallel plates and its frequency spectrum
AIP Advances, 2018Co-Authors: Zongxin Wang, Fei YangAbstract:Antennas in the ultra low frequency (ULF, 300 Hz to 3 kHz) and very low frequency (VLF, 3∼30 kHz) bands are usually very large. In this study, we developed a very small antenna, which can radiate electromagnetic waves in these frequency bands. The antenna consisted of two rotating charged plates (RCPs), which were charged by the voltage source. Numerical results of the Radiated far Field and its frequency spectrum are presented for three cases: (a) the antenna is charged with DC voltage, (b) the antenna is charged with AC voltage, and (c) the antenna rotates with variable speed and is fed with DC voltage. The predominant frequency component was equal to the rotating frequency of the RCPs fed with DC voltage. If the RCPs were fed with AC voltage two dominant frequencies were generated, which were determined by the difference in frequency between the RCP rotation frequency and the AC source frequency. When the RCPs rotated with variable speed and were fed with DC voltage, many frequency components were gene...
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Radiated Field of rotating charged parallel plates and its frequency spectrum
AIP Publishing LLC, 2018Co-Authors: Zongxin Wang, Zhenxin Cao, Fei YangAbstract:Antennas in the ultra low frequency (ULF, 300 Hz to 3 kHz) and very low frequency (VLF, 3∼30 kHz) bands are usually very large. In this study, we developed a very small antenna, which can radiate electromagnetic waves in these frequency bands. The antenna consisted of two rotating charged plates (RCPs), which were charged by the voltage source. Numerical results of the Radiated far Field and its frequency spectrum are presented for three cases: (a) the antenna is charged with DC voltage, (b) the antenna is charged with AC voltage, and (c) the antenna rotates with variable speed and is fed with DC voltage. The predominant frequency component was equal to the rotating frequency of the RCPs fed with DC voltage. If the RCPs were fed with AC voltage two dominant frequencies were generated, which were determined by the difference in frequency between the RCP rotation frequency and the AC source frequency. When the RCPs rotated with variable speed and were fed with DC voltage, many frequency components were generated, which were determined by the initial rotational speed of the RCPs and their acceleration