Browsing by Author "Lin, Wen-Piao"

Now showing 1 - 11 of 11

62nm CW wavelength-selectable erbium-doped fiber compound-ring laser with stable single-mode output
(2019-12-01)
Yeh, Chien-Hung
;
Chang, Yao-Jen
;
Lin, Wen-Piao
;
Xie, Yue-Ru
;
Luo, Chien-Ming
In this demonstration, an erbium-doped fiber (EDF) based laser with stable, wide and wavelength-selectable single-longitudinal-mode (SLM) performances is designed and demonstrated. Here, to achieve SLM oscillation, a compound-ring scheme is constructed in the EDF laser cavity serving as a mode-restriction-filter for densely side-mode suppression. Moreover, the continuous-wave tunability can be scaled from 1520.0 to 1582.0 nm by using the proposed compound-ring scheme and commercial C-band EDF amplifier. In the measurement, the output stability and 3 dB Lorentzian linewidth of each lasing wavelength in the proposed EDF compound-ring laser have also been discussed.
A Selectable Single-Mode Erbium Laser With Power-Flattened Output Employing Dual-Sagnac-Ring
(2019-01-01)
Yeh, Chien-Hung
;
Lin, Wen-Piao
;
Chang, Yao-Jen
;
Xie, Yue-Ru
;
Luo, Chien-Ming
To achieve wavelength-selectable and stable erbium-doped fiber (EDF) laser, a dual-Sagnac-ring configuration is designed to reach single-longitudinal-mode (SLM) oscillation and power-flattened output simultaneously. The presented and experimentally demonstrated EDF laser can also obtain the output power of 7.5 to 11.8 dBm in the continuous-wave (CW) tunability of 1523.0 to 1571.0 nm. Here, the power variation of lasing wavelength can be below than 1.0 dB over a wide working range of 1525.0-1565.0 nm for power-flattened output. Moreover, the 3-dB spectrum linewidth of presented EDF-based laser is measured in the range of 16.4-22.2 kHz via the Lorentzian fitting.
An Erbium Fiber Laser With Single-Frequency Oscillation and Wavelength-Upconverted Output
(2020-10-01)
Yeh, Chien-Hung
;
You, Wei-Yao
;
Chen, Jhao-Ren
;
Chow, Chi-Wai
;
Lin, Wen-Piao
In this paper, we present experimentally an erbium-doped fiber (EDF) laser system to accomplish the single-longitudinal-mode (SLM) and wavelength-upconverted output by using nonlinear effect. To accomplish the SLM output, a short length of unpumped EDF saturable absorber (SA) is applied inside the EDF laser cavity for filtering densely multi-mode noise. In accordance with the designed EDF laser system, the lasing wavelength can be upconverted to a longer wavelength position. In addition, the output characteristics of output power, optical signal to noise ratio (OSNR), tunability, stability and linewidth in the EDF laser are also discussed.
Free Space Optical Communication in Long-Reach Unidirectional Ring-Architecture Fiber Network
(2020-01-01)
Yeh, Chien-Hung
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Chen, Jhao-Ren
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You, Wei-Yao
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Lin, Wen-Piao
;
Chow, Chi-Wai
In the work, a ring-constructed wavelength-division-multiplexing (WDM) access system for delivering multiple free space optical (FSO) wireless signals is investigated. To reach the FSO transmission through single-mode fiber (SMF) connection, the optical wireless unit (OWU) and remote OWU are designed in the WDM network. The downstream and upstream WDM FSO channels could be transmitted in unidirectional propagation with the same wavelength. Hence, the presented ring-based WDM network not only can transmit the FSO signal, but also can circumvent the Rayleigh backscattering (RB) interferometric beat noise. In addition, according to the experimental results, the SMF and FSO transmission lengths can reach 50 km and 500 to 1000 m at the forward error correction (FEC) level without using optical amplification and dispersion compensation, respectively, when four WDM wavelengths are exploited experimentally for demonstration.
Rayleigh Backscattering Noise Alleviation in Long-Reach Ring-Based WDM Access Communication
(2020-01-01)
Yeh, Chieg-Hua
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Chen, Jhao-Ren
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You, Wei-Yao
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Lin, Wen-Piao
;
Chow, Chi-Wai
In the paper, we propose and design a ring-topology wavelength-division-multiplexing (WDM) access network for long-reach signal transmission. Here, the new central office (CO) and optical network unit (ONU) modules are designed to construct the ring-based architecture for symmetric data connection. Thus, the Rayleigh backscattering (RB) beat noise can be prevented due to the unidirectional downstream and upstream signal connections. In the demonstration, eight WDM wavelengths with 10 Gbit/s on-off keying (OOK) modulation are applied to serve as the symmetric downstream and upstream traffic through 105 km fiber connection without dispersion compensation. In addition, the minimum power budgets of 33.8, 36.1 and 35.4 dB among the eight WDM wavelengths can be obtained at the back-to-back (BtB), 51 and 105 km fiber links, respectively, under the forward error correction (FEC) target.
Self-healing fiber Bragg grating sensor system
(2005-11-10)
Chi, Sien
;
Peng, Peng-Chun
;
Lin, Wen-Piao
The present invention is a self-healing fiber Bragg grating sensor system which comprises a central office, at least one network node, at least one 2×2 optical switch and at least one fiber Bragg grating. The network node can be made of optical switch. When the fiber for the sensor system is broken, sensing signals are discriminated in different paths provided by the network nodes to avoid stop working once the fiber is broken, by which the self-healing ability of the system is greatly improved. Besides, by using the structure of fiber laser in the present invention, the power output and the signal-to-noise ratio can be greatly increased. Accordingly, the present invention is to design a fiber sensor system with low cost and high capacity and with capability of self-healing.
Use of Same WDM Channels in Fiber Network for Bidirectional Free Space Optical Communication With Rayleigh Backscattering Interference Alleviation
(2019-01-01)
Yeh, Chien-Hung
;
Guo, Bo-Shen
;
Gu, Chong-Sin
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Chow, Chi-Wai
;
Lin, Wen-Piao
In the paper, we present and demonstrate experimentally a 10 Gbit/s on-off keying (OOK) bidirectional wavelength-division-multiplexing (WDM) free space optical (FSO) communication architecture integrated in fiber network together with 5 m free space transmission length and 25 km fiber link, respectively. To achieve bidirectional FSO link, the all WDM wavelengths can be used simultaneously to serve as the downstream and upstream traffics in the proposed FSO-WDM system. Here, four pairs of line terminations (LTs) and optical wireless units (OWUs) are integrated arbitrarily in fiber access network for confidential and bidirectional FSO connection based on the requirement of practical environment. In the measurement, the relationship of FSO signal performance and detected tolerance are also discussed and analyzed. Moreover, the WDM-FSO transmission can also avoid the Rayleigh backscattering (RB) beat noise in fiber connection.
Use of Same WDM Channels in Fiber Network for Bidirectional Free Space Optical Communication With Rayleigh Backscattering Interference Alleviation
(2019-01-01)
Yeh, Chien-Hung
;
Guo, Bo-Shen
;
Gu, Chong-Sin
;
Chow, Chi-Wai
;
Lin, Wen-Piao
In the paper, we present and demonstrate experimentally a 10 Gbit/s on-off keying (OOK) bidirectional wavelength-division-multiplexing (WDM) free space optical (FSO) communication architecture integrated in fiber network together with 5 m free space transmission length and 25 km fiber link, respectively. To achieve bidirectional FSO link, the all WDM wavelengths can be used simultaneously to serve as the downstream and upstream traffics in the proposed FSO-WDM system. Here, four pairs of line terminations (LTs) and optical wireless units (OWUs) are integrated arbitrarily in fiber access network for confidential and bidirectional FSO connection based on the requirement of practical environment. In the measurement, the relationship of FSO signal performance and detected tolerance are also discussed and analyzed. Moreover, the WDM-FSO transmission can also avoid the Rayleigh backscattering (RB) beat noise in fiber connection.
Utilizing polarization-multiplexing for free space optical communication transmission with security operation
(2019-11-01)
Yeh, Chien-Hung
;
Chang, Yao-Jen
;
Chow, Chi-Wai
;
Lin, Wen-Piao
;
光電工程學系
In this study, we present and demonstrate a 10 Gbit/s on-off keying (OOK) free space optical communication (FSO) system with signal security operation by using polarization-multiplexing method. A single wavelength can be separated two orthogonal polarization FSO signals, which mean the FSOp and FSOs respectively, by using two polarizers with mutually orthogonal polarization directions. And the FSOp and FSOs wavelengths can act as the data and interference channels for FSO connection. When the injected power of FSOs is > -30 dBm, the FSOp signal will be interfered seriously for security protection. In addition, the FSO signal can pass through 25 km fiber link and support 1000 m free space transmission length.
Utilizing self-injection Rayleigh backscattering feedback for channel-selected erbium laser with single-longitudinal-mode output
(2020-07-01)
Yeh, Chien-Hung
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You, Wei-Yao
;
Chen, Jhao-Ren
;
Chow, Chi-Wai
;
Lin, Wen-Piao
To achieve the target of single-longitudinal-mode (SLM) operation in erbium-doped fiber (EDF) laser, a self-injected Rayleigh backscattering (RBS) feedback schematic is proposed and demonstrated experimentally. Based on the proposed RBS effect, the multi-longitudinal-mode (MLM) noises of the RBS EDF laser can be suppressed fully. Here, the output powers of -7.5 to -5.1 dBm are detected over the tuning bandwidth of 1523.0 to 1563.0 nm. Moreover, the optical signal to noise ratios (OSNRs) of 30.9 and 33.1 dB is also attained. In this study, the SLM oscillation and output instability of the EDF laser are also analyzed and discussed.
Utilizing Single Lightwave for Delivering Baseband/FSO/MMW Traffics Simultaneously in PON Architecture
(2019-01-01)
Yeh, Chien-Hung
;
Lin, Wen-Piao
;
Luo, Chien-Ming
;
Xie, Yue-Ru
;
Chang, Yao-Jen
In this work, we demonstrate an integrated optical baseband, free space optical (FSO) communication and millimeter-wave (MMW) traffics through the present passive optical network (PON) architecture by utilizing single wavelength for broadcasting triple-play services. In the execution, we exploit 10 Gbit/s on-off keying (OOK) modulation on 10 GHz Mach-Zehnder modulator (MZM) to produce the downstream baseband signal. And the 10 Gbit/s baseband signal also can cause FSO traffic within the forward error correction (FEC) target after 25 km fiber and 160 m free space transmissions. Moreover, we can utilize the fiber to the extension (FTTE) scheme to provide the 36.42 GHz MMW with 10 Gbit/s OOK data after 25 km fiber link and 8 km extended fiber transmission.