Browsing by Author "Wang, Chia-Hsuan"

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Fiber sensing system with self-detection mechanism
(2010-07-22)
Chow, Chi-Wai
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Chi, Sien
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Wang, Chia-Hsuan
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Shih, Fu-Yuan
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Yeh, Chein-Hung
The present invention discloses a fiber sensing system with self-detection mechanism which utilizes a central office to control secondary ring architecture formed by fiber sensor, remote node and optical coupler primarily. The secondary ring architecture is connected serially to form a primary ring architecture. The central office has a tunable laser light source that can deliver the light source to the fiber sensor. Since the fiber sensor has reflective ability, all light source signal sent by the tunable laser light source will be detected and measured by the fiber sensor. Thus central office can detect all signals reflected by the fiber sensor and produce a spectrum for analyzing fault point locations. The present invention can greatly enhance survivability and sensing capacity of all fiber sensors, so that when a fault point caused by environmental change within the fiber, it will not effect the overall operation of the sensing mechanism. The application of fiber sensor can also reduce cost and complexity of the overall fiber network topology.
Tunable Dual-Wavelength Fiber Laser Using Optical-Injection Fabry-Perot Laser
(2008-11-01)
Yeh, Chien-Hung
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Chow, Chi-Wai
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Shih, Fu-Yuan
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Wang, Chia-Hsuan
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Wu, Yu-Fu
In this investigation, we propose and experimentally demonstrate a dual-wavelength fiber laser based on a self-injected Fabry-Perot laser diode and an erbium-doped fiber. The dual-wavelength tuning range is 39.49 nm, from 1526.27 to 1565.76 nm. And the mode spacing of the dual-wavelength can be tuned from 1.32 to 39.49 nm. In addition, the output power difference of the dual-wavelength can be controlled and smaller than 1 dB.
Tunable Dual-Wavelength Fiber Laser Using Optical-Injection Fabry-Perot Laser
(2009-01-01)
Yeh, Chien-Hung
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Chow, Chi-Wai
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Shih, Fu-Yuan
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Wang, Chia-Hsuan
;
Wu, Yu-Fu
In this investigation, we propose and experimentally demonstrate a dual-wavelength fiber laser based on a self-injected Fabry-Perot laser diode and an erbium-doped fiber. The dual-wavelength tuning range is 39.49 run, from 1526.27 to 1565.76 nm, and the mode spacing of the dual-wavelength can be tuned from 1.32 to 39.49 run. In addition, the output power difference of the dual-wavelength can be controlled and smaller than 1 dB.
Using OOK Modulation for Symmetric 40-Gb/s Long-Reach Time-Sharing Passive Optical Networks
(2010-05-01)
Yeh, Chien-Hung
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Chow, Chi-Wai
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Wang, Chia-Hsuan
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Wu, Yu-Fu
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Shih, Fu-Yuan
Due to the requirement of broad bandwidth for next-generation access networks, present passive optical networks (PONs) will be upgraded to 40 Gb/s or higher data rate PONs. Hence, we propose and experimentally demonstrate a simple and efficient scheme to achieve a symmetric 40-Gb/s long-reach (LR) time-division-multiplexed PON by using four wavelength-division-multiplexed 10-Gb/s external on-off keying format channels to serve as the optical transmitter for downstream and upstream traffic simultaneously. Moreover, the system performance of LR transmission and split ratio have also been analyzed and discussed without dispersion compensation.
WDM extended reach passive optical networks using OFDM-QAM
(2008-08-04)
Chow, Chi-Wai
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Yeh, Chien-Hung
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Wang, Chia-Hsuan
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Shih, Fu-Yuan
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Pan, Ci-Ling
In order to reduce the cost for delivering future broadband services, network operators are inclined to simplify the network architectures by integrating the metro and access networks into a single system. Hence, extended reach passive optical networks (ER-PONs) have been proposed. ER-PON usually has four new features: high data rate in both upstream and downstream signals (> 1 Gb/s); reach extension to > 100 km; a high split ratio (> 100); and using wavelength division multiplexing (WDM). In this work, we propose and demonstrate a highly spectral efficient ER-PON using 4 Gb/s OFDM-QAM for both upstream and downstream signals, while achieving a high split-ratio of 256. The ER-PON employs optical components optimized for GPON (bandwidth of similar to 1GHz) and reaches 100 km without dispersion compensation. Numerical analysis using 16, 64 and 256-QAM OFDM are also performed to study the back-to-back receiver sensitivities and power penalties at different electrical driving ratios. (C) 2008 Optical Society of America.