The Experts below are selected from a list of 143136 Experts worldwide ranked by ideXlab platform
Gee-kung Chang - One of the best experts on this subject based on the ideXlab platform.
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optical signal processing for w band radio over Fiber System with tunable frequency response
IEEE Journal of Selected Topics in Quantum Electronics, 2021Co-Authors: Runkai Shiu, Youwei Chen, Pengchun Peng, Minghan Wen, Chinwei Hsu, Gee-kung ChangAbstract:Tunable frequency response is designed and experimentally demonstrated in this paper. The performance of frequency response in proposed radio-over-Fiber (RoF) Systems is investigated in terms of theoretical analysis, simulations, and experimental results with various Fiber transmission distances. The notch in frequency response can be easily circumvented by changing the oriented angle of polarized lightwave in the proposed direct detection (DD) scheme. For comparison, the conventional Mach-Zehnder modulator (MZM) based DD scheme suffers from fixed frequency notch at certain frequencies, which generates forbidden frequency bands for W-band signal delivery. Our experimental results show that the proposed DD scheme exhibits a stable EVM performance of the 16-QAM signal from 83 GHz to 87 GHz via 25-km standard single-mode Fiber (SSMF) and 1-m wireless transmission. On the contrary, the conventional MZM-based DD scheme encounters severe signal degradation at 85 GHz and 86 GHz. In this paper, the proposed scheme is implemented to demonstrate full bandwidth availability within a desirable frequency range by tuning the frequency response. Furthermore, a 10-Gbps 16-QAM signal located at 85 GHz is successfully transmitted by the proposed DD scheme which can provide 10-gigabit data transmission under 5G requirement.
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centralized digital self interference cancellation technique to enable full duplex operation of next generation millimeter wave over Fiber Systems
Optical Fiber Communication Conference, 2020Co-Authors: Qi Zhou, Youwei Chen, Shuyi Shen, Shuang Yao, Yahya Alfadhli, Gee-kung ChangAbstract:We propose and experimentally demonstrate a centralized digital self-interference cancellation scheme in a mm-wave over Fiber System for full-duplex next-generation mobile networks. A 24.1-dB self-interference cancellation over 1-GHz bandwidth is realized with successful signal-of-interest recovery.
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millimeter wave cell grouping for optimized coverage based on radio over Fiber and centralized processing
Optical Fiber Communication Conference, 2016Co-Authors: Lin Cheng, Jing Wang, Junwen Zhang, Gee-kung ChangAbstract:We propose and experimentally demonstrate a cell grouping method to improve frequency-reused millimeter-wave coverage. The method provides a 3.5-dB improvement on signal quality and power budget in a field test on a three-transmitter radio-over-Fiber System.
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bidirectional multiband radio over Fiber System based on polarization multiplexing and wavelength reuse
Optics Express, 2015Co-Authors: Jianyu Zheng, Min Zhang, Xue Chen, Gee-kung ChangAbstract:A polarization multiplexing technique based on phase-shift-induced polarization modulation-to-intensity modulation (PloM-to-IM) convertor and a Mach-Zehnder modulator (MZM) is proposed to generate multi-band signals. Successful transmission of the traditional radio frequency, microwave (MW) and millimeter wave (MMW) signals is simultaneously achieved. Meanwhile, the intensity-constant optical carrier (OC) is reused for upstream 25-km transmission.
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a bi directional radio over Fiber System with all optical up converted dpsk for downstream and re modulated ook for upstream
Lasers and Electro-Optics Society Meeting, 2006Co-Authors: Zhensheng Jia, M Haris, D Boivin, Gee-kung ChangAbstract:We propose and demonstrate a novel full-duplex radio-over-Fiber System using OOK re-modulation of up-converted downstream DPSK signal for upstream connection. The bi-directional 2.5 Gbits/s data is successfully transmitted over 40 km SMF-28 with <2 dB power penalty
Linda Partridge - One of the best experts on this subject based on the ideXlab platform.
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a computational model of the escape response latency in the giant Fiber System of drosophila melanogaster
eNeuro, 2019Co-Authors: Asaph Zylbertal, Hrvoje Augustin, Linda PartridgeAbstract:Abstract The giant Fiber System (GFS) is a multi-component neuronal pathway mediating rapid escape response in the adult fruit-fly Drosophila melanogaster, usually in the face of a threatening visual stimulus. Two branches of the circuit promote the response by stimulating an escape jump followed by flight initiation. A recent work demonstrated an age-associated decline in the speed of signal propagation through the circuit, measured as the stimulus-to-muscle depolarization response latency. The decline is likely due to the diminishing number of inter-neuronal gap junctions in the GFS of ageing flies. In this work, we presented a realistic conductance-based, computational model of the GFS that recapitulates the experimental results and identifies some of the critical anatomical and physiological components governing the circuit’s response latency. According to our model, anatomical properties of the GFS neurons have a stronger impact on the transmission than neuronal membrane conductance densities. The model provides testable predictions for the effect of experimental interventions on the circuit’s performance in young and ageing flies.
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a computational model of the escape response latency in the giant Fiber System of drosophila melanogaster
bioRxiv, 2018Co-Authors: Asaph Zylbertal, Hrvoje Augustin, Linda PartridgeAbstract:ABSTRACT The Giant Fiber System (GFS) is a multi-component neuronal pathway mediating rapid escape response in the adult fruit-fly Drosophila melanogaster, usually in the face of a threatening visual stimulus. Two branches of the circuit promote the response by stimulating an escape jump followed by flight initiation. Our recent work demonstrated an age-associated decline in the speed of signal propagation through the circuit, measured as the stimulus-to-muscle depolarization response latency. The decline is likely due to the diminishing number of interneuronal gap junctions in the GFS of ageing flies. In this work, we presented a realistic conductance-based, computational model of the GFS that recapitulates our experimental results and identifies some of the critical anatomical and physiological components governing the circuit’s response latency. According to our model, anatomical properties of the GFS neurons have a stronger impact on the transmission than neuronal membrane conductance densities. The model provides testable predictions for the effect of experimental interventions on the circuit’s performance in young and ageing flies.
Hrvoje Augustin - One of the best experts on this subject based on the ideXlab platform.
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a computational model of the escape response latency in the giant Fiber System of drosophila melanogaster
eNeuro, 2019Co-Authors: Asaph Zylbertal, Hrvoje Augustin, Linda PartridgeAbstract:Abstract The giant Fiber System (GFS) is a multi-component neuronal pathway mediating rapid escape response in the adult fruit-fly Drosophila melanogaster, usually in the face of a threatening visual stimulus. Two branches of the circuit promote the response by stimulating an escape jump followed by flight initiation. A recent work demonstrated an age-associated decline in the speed of signal propagation through the circuit, measured as the stimulus-to-muscle depolarization response latency. The decline is likely due to the diminishing number of inter-neuronal gap junctions in the GFS of ageing flies. In this work, we presented a realistic conductance-based, computational model of the GFS that recapitulates the experimental results and identifies some of the critical anatomical and physiological components governing the circuit’s response latency. According to our model, anatomical properties of the GFS neurons have a stronger impact on the transmission than neuronal membrane conductance densities. The model provides testable predictions for the effect of experimental interventions on the circuit’s performance in young and ageing flies.
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a computational model of the escape response latency in the giant Fiber System of drosophila melanogaster
bioRxiv, 2018Co-Authors: Asaph Zylbertal, Hrvoje Augustin, Linda PartridgeAbstract:ABSTRACT The Giant Fiber System (GFS) is a multi-component neuronal pathway mediating rapid escape response in the adult fruit-fly Drosophila melanogaster, usually in the face of a threatening visual stimulus. Two branches of the circuit promote the response by stimulating an escape jump followed by flight initiation. Our recent work demonstrated an age-associated decline in the speed of signal propagation through the circuit, measured as the stimulus-to-muscle depolarization response latency. The decline is likely due to the diminishing number of interneuronal gap junctions in the GFS of ageing flies. In this work, we presented a realistic conductance-based, computational model of the GFS that recapitulates our experimental results and identifies some of the critical anatomical and physiological components governing the circuit’s response latency. According to our model, anatomical properties of the GFS neurons have a stronger impact on the transmission than neuronal membrane conductance densities. The model provides testable predictions for the effect of experimental interventions on the circuit’s performance in young and ageing flies.
Shigeki Yuasa - One of the best experts on this subject based on the ideXlab platform.
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involvement of highly polysialylated neural cell adhesion molecule psa ncam positive granule cells in the amygdaloid kindling induced sprouting of a hippocampal mossy Fiber trajectory
Neuroscience Research, 2004Co-Authors: Takashi Saegusa, Seiichiro Mine, Hiroto Iwasa, Hisayuki Murai, Tatsunori Seki, Akira Yamaura, Shigeki YuasaAbstract:The mossy Fiber System in the hippocampus of amygdaloid-kindled rats was examined by using highly polysialylated neural cell adhesion molecule (PSA-NCAM) as a marker for immunohistochemical detection of immature dentate granule cells and mossy Fibers in combination with bromodeoxyuridine (BrdU) labeling of newly generated granule cells. Statistically significant increases in BrdU-labeled cells and PSA-NCAM-positive cells occurred in the dentate gyrus following kindling. The increase in PSA-NCAM-immunoreactive neurites was confined to the entire stratum lucidum of CA3. Immunoelectron-microscopic examination also revealed that PSA-NCAM-positive immature synaptic terminals of the sprouting mossy Fibers increased in the stratum lucidum of CA3 in the kindled rats. The increase in the numbers of PSA-NCAM-positive granule cells correlated well with the increase in the immunopositive neurites and synaptic terminals on the mossy Fiber trajectory. The increase in these PSA-NCAM-immunopositive structures is thought to reflect the enhancement of sprouting and synaptogenesis of mossy Fibers by a subset of granule cells newly generated during amygdaloid-kindling and suggests that the reorganization of the mossy Fiber System on the normal trajectory at least in part contributes to the acquisition and maintenance of an epileptogenic state.
Cozic Solenn - One of the best experts on this subject based on the ideXlab platform.
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2–10 µm Mid‐Infrared Fiber‐Based Supercontinuum Laser Source: Experiment and Simulation
HAL CCSD, 2020Co-Authors: Venck Sebastien, St-hilaire François, Brilland L, Ghosh, Amar Nath, Chahal Radwan, Caillaud Céline, Meneghetti Marcello, Troles J, Joulain Franck, Cozic SolennAbstract:International audienceMid‐infrared supercontinuum (mid‐IR SC) sources in the 2–20 µm molecular fingerprint region are in high demand for a wide range of applications including optical coherence tomography, remote sensing, molecular spectroscopy, and hyperspectral imaging. Herein, mid‐IR SC generation is investigated in a cascaded silica‐ZBLAN‐chalcogenide Fiber System directly pumped with a commercially available pulsed Fiber laser operating in the telecommunications window at 1.55 µm. This Fiber‐based System is shown to generate a flat broadband mid‐IR SC covering the entire range from 2 to 10 µm with several tens of mW of output power. This technique paves the way for low cost, practical, and robust broadband SC sources in the mid‐IR without the requirement of mid‐infrared pump sources or Thulium‐doped Fiber amplifiers. A fully realistic numerical model used to simulate the nonlinear pulse propagation through the cascaded Fiber System is also described and the numerical results are used to discuss the physical processes underlying the spectral broadening in the cascaded System. Finally, recommendations are provided for optimizing the current cascaded System based on the simulation result
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2-10 mu m Mid-Infrared Fiber-Based Supercontinuum Laser Source: Experiment and Simulation
'Wiley', 2020Co-Authors: Venck Sebastien, St-hilaire François, Chahal Radwan, Caillaud Céline, Meneghetti Marcello, Joulain Franck, Brilland Laurent, Ghosh, Amar N., Troles Johann, Cozic SolennAbstract:International audienceMid-infrared supercontinuum (mid-IR SC) sources in the 2-20 mu m molecular fingerprint region are in high demand for a wide range of applications including optical coherence tomography, remote sensing, molecular spectroscopy, and hyperspectral imaging. Herein, mid-IR SC generation is investigated in a cascaded silica-ZBLAN-chalcogenide Fiber System directly pumped with a commercially available pulsed Fiber laser operating in the telecommunications window at 1.55 mu m. This Fiber-based System is shown to generate a flat broadband mid-IR SC covering the entire range from 2 to 10 mu m with several tens of mW of output power. This technique paves the way for low cost, practical, and robust broadband SC sources in the mid-IR without the requirement of mid-infrared pump sources or Thulium-doped Fiber amplifiers. A fully realistic numerical model used to simulate the nonlinear pulse propagation through the cascaded Fiber System is also described and the numerical results are used to discuss the physical processes underlying the spectral broadening in the cascaded System. Finally, recommendations are provided for optimizing the current cascaded System based on the simulation results