Browsing by Author "Chen, Li-Wei"

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224-Gbps Transmission for Next-Generation WDM Long-Reach PON Using CAP Modulation
(2016)
Chen, Kuan-Zhou
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Chen, Li-Wei
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Lin, Che-Yu
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Huang, Wan-Jou
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Wei, Chia-Chien
Leveraging high transmission bandwidth and loss budget provided by high launch power, we experimentally demonstrate 4-lambda 224-Gbps 32-CAP 60-km transmission using cost-effective 10-GHz-class EAM/PIN, supporting > 3-Gbps/ONU for a 64-ONU LR-PON, without inline and pre-amplifier.
A 200-Gbps OFDM Long-Reach PON over 60-km Transmission without Inline and Pre-Amplifier
(2015)
Chen, Hsing-Yu
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Wei, Chia-Chien
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Lin, Che-Yu
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Chen, Li-Wei
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Lu, I-Cheng
200-Gbps 60-km OFDM transmission in a 4-channel WDM system is demonstrated with 29-dB loss budget per channel without inline and pre-amplifier. Employing 10-GHz EAM and PIN, the LR-PON can support 64 ONUS with >2.5-Gbps/ONU capacity.
Frequency - and time-domain nonlinear distortion compensation in high-speed OFDM-IMDD LR-PON with high loss budget
(2017-03-06)
Chen, Hsing-Yu
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Wei, Chia-Chien
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Lin, Che-Yu
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Chen, Li-Wei
;
Lu, I-Cheng
This study compared two nonlinear distortion compensation techniques, SSII cancellation (in the frequency domain) and Volterra filtering (in the time domain), in a > 50-Gbps/lambda OFDM-IMDD LR-PON. Experiment results for SNR, BER, and data rate (based on a bit-loading algorithm) revealed that the performance of frequency-domain SSII cancellation is unaffected by power fading; however, it depends heavily on the precision of the mathematical model. Conversely, although time-domain Volterra filtering is affected by the faded waveform, adaptive-weighting provides flexibility in dealing with mixed nonlinear distortion, particularly that associated with the interplay between fiber dispersion and fiber nonlinearity. 4-channel WDM-OFDM and 3rd-order Volterra filtering were used to demonstrate the feasibility of the proposed scheme in a 200-Gbps IMDD system. Based on 10-GHz EAM and PIN, we achieved 200-Gbps transmission over a distance of 60 km with a loss budget of > 30 dB, while providing support for 128 ONUs at >1.6 Gbps/ONU without the need for an inline amplifier or pre-amplifier. (C) 2017 Optical Society of America
High-Capacity Carrierless Amplitude and Phase Modulation for WDM Long-Reach PON Featuring High Loss Budget
(2017-02-15)
Wei, Chia-Chien
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Chen, Kuan-Zhou
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Chen, Li-Wei
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Lin, Che-Yu
;
Huang, Wan-Jou
This paper utilizes spectrally efficient carrierless amplitude and phase (CAP) modulation and four wavelength division multiplexing channels in formulation of a high-capacity transmission system. The dispersion and loss associated with a single-mode fiber of 60 km can result in severe power fading and insufficient loss budget, respectively. This study employed high launch power to overcome these issues and thereby achieve long-reach transmission without the need for dispersion compensation or an optical inline amplifier. Modified Volterra filtering is used to deal with the linear and nonlinear distortions within the system. This allowed for the inclusion of cost-effective 10-GHz-class electro-absorption modulators and p-i-n detectors for 4-lambda 224-Gb/s 32-CAP 60-km transmission with a loss budget of 26 dB/channel. The proposed system provides support for the 64 optical network units (ONUs) with downstream transmission of > 3 Gb/s/ONU for future long-reach passive optical networks. We also examined the transmission performance of each channel under various launch powers. Increasing launch power from 9 to 18 dBm/channel increases the loss budget by 9 dB and expands the total capacity by 42%.
New experimental evidence to support roaming in the reaction Cl plus isobutene (i-C4H8)
(2017-01-12)
Chen, Li-Wei
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Hung, Ching-Ming
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Matsui, Hiroyuki
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Lee, Yuan-Pern
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應用化學系
The reaction Cl + isobutene (i-C4H8) was reported by Suits et al. to proceed via, in addition to abstraction, an addition-elimination path following a roaming excursion of Cl; a near-zero translational energy release and an isotropic angular distribution observed at a small collision energy characterized this mechanism. We employed a new experimental method to further characterize this roaming mechanism through observation of the internal distribution of HCl (v, J) and their temporal behavior upon irradiation of a mixture of Cl2C2O2 and i-C4H8 in He or Ar buffer gas. With 1-3 Torr buffer gas added to approach the condition of small collision energy, the intensities of emission of HCl (v = 1, 2) and the HCl production rates increased significantly; Ar shows a more significant effect than He because Ar quenches Cl more efficiently to reduce the collisional energy and facilitate the roaming path. According to kinetic modeling, the rate of addition-elimination (roaming) increased from k(E) approximate to 2 x 10(5) s(-1) when little buffer gas was present to similar to 1.9 x 106 s(-1) when 2-3 Torr of Ar was added, and the branching ratio for formation of [HCl (v = 2)]/[ HCl (v = 1)] increased from 0.02 +/- 0.01 for abstraction to 0.06 +/- 0.01 for roaming.
Simultaneous Infrared Detection of the ICH2OO Radical and Criegee Intermediate CH2OO: The Pressure Dependence of the Yield of CH2OO in the Reaction CH2I + O-2
(2015-11-19)
Huang, Yu-Hsuan
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Chen, Li-Wei
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Lee, Yuan-Pern
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應用化學系
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應用化學系分子科學碩博班
The simplest Criegee intermediate CH2OO, important in atmospheric reactions, has been recently produced from the reaction of CH2I + O-2 and detected with various methods. In this reaction, the yield of CH2OO decreases with increasing pressure because of the stabilization of the adduct ICH2OO, but no definitive spectral identification of ICH2OO has been reported. We recorded the infrared spectrum of ICH2OO using the same reaction under high pressure; the spectrum agrees with that simulated according to theoretical predictions. With direct detection of both CH2OO and ICH2OO, we determined the pressure dependence of the yield of CH2OO. The yield of CH2OO near 1 atm is greater than previously reported values, which might have significant consequences in atmospheric chemistry.