Browsing by Author "WEN, SF"

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APPROXIMATE SOLUTION OF OPTICAL SOLITON IN LOSSLESS FIBERS WITH 3RD-ORDER DISPERSION
(1989-07-01)
WEN, SF
;
CHI, S
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交大名義發表
;
光電工程學系
;
National Chiao Tung University
CHARACTERISTICS OF THE GAIN AND SIGNAL-TO-NOISE RATIO OF A DISTRIBUTED ERBIUM-DOPED FIBER AMPLIFIER
(1992-12-01)
WEN, SF
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CHI, S
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光電工程學系
;
Department of Photonics
The effects of the stimulated Ramam scattering (SRS) on the gain and signal-to-noise ratio (SNR) of the DEDFA with 100-km fiber length and with bidirectional pumps are numerically studied. It is found that the gain and SNR are significantly enhanced by the SRS with practical parameters. For 1.55-mum signal and 10-muW initial signal power, there are 8.8-dB gain enhancement and 3.3-dB SNR enhancement for 1.48-mum pump wavelength and 75-mW initial pump power. The characteristics of the gain and SNR enhancements due to SRS are studied for different signal wavelength, signal powers, pump wavelengths, pump powers, and effective fiber cross sections. The results show that the gain and SNR are decreased by SRS only for the unpractical high pump power and/or small effective fiber cross section.
EFFECT OF CROSS-PHASE MODULATION ON OPTICAL-PHASE CONJUGATION IN DISPERSION-SHIFTED FIBER
(1994-07-01)
WEN, SF
;
CHI, S
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CHANG, TC
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光電工程學系
;
Department of Photonics
The temporal effect of optical phase conjugation in dispersion-shifted fiber is studied numerically. Frequency chirping is induced in the conjugate pulse by the signal pulse and the pump wave through cross-phase modulation, which increases with the signal power and may distort the pulse shape when the conjugate pulse propagates in the standard fiber. It is also shown that, when the signal power is low, the optical phase conjugation is nearly ideal.
IMPROVING THE UNDOING OF SOLITON INTERACTION WITH OPTICAL-PHASE CONJUGATION BY PHASE ALTERNATION BETWEEN NEIGHBORING SOLITONS
(1995-05-15)
CHI, S
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DUNG, JC
;
WEN, SF
;
光電工程學系
;
電信研究中心
The undoing of the soliton interaction with the optical phase conjugation by the phase alternation between neighboring solitons is numerically studied. When the phase alternation is larger than 90-degrees, the undoing of the soliton interaction is good even when the conjugation is applied at the distance where the solitons interact seriously.
OPTICAL SOLITON NEAR ZERO-DISPERSION REGIME IN A RAMAN PUMPED FIBER
(1989-01-01)
CHI, S
;
WEN, SF
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
RAMAN CROSS TALK OF SOLITON COLLISION IN A LOSSLESS FIBER
(1989-11-01)
CHI, S
;
WEN, SF
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
RECOVERY OF THE SOLITON SELF-FREQUENCY SHIFT BY OPTICAL-PHASE CONJUGATION
(1994-11-01)
CHI, S
;
WEN, SF
;
光電工程學系
;
Department of Photonics
The recovery of the self-frequency shift effect on a soliton by optical phase conjugation is investigated. It is proved that, without third-order dispersion and fiber loss, the soliton self-frequency shift can be completely recovered. The recoveries for a fundamental soliton and a second-order soliton in the presence of third-order dispersion and of fiber loss, which is compensated by the distributed erbium-doped fiber amplifiers, are numerically studied.
REDUCTION OF SOLITON-INTERACTIONS BY ZIGZAG-SLIDING-FREQUENCY GUIDING FILTERS
(1995-09-15)
DUNG, JC
;
CHI, S
;
WEN, SF
;
光電工程學系
;
Department of Photonics
Reductions of the soliton interactions and jitter by the upsliding-frequency filter, the downsliding-frequency filter, and the zigzag-sliding-frequency filter are numerically studied. It is shown that the most effective filter for reducing the soliton interactions is the zigzag-sliding-frequency filter. (C) 1995 Optical Society of America
REDUCTION OF SOLITON-INTERACTIONS BY ZIGZAG-SLIDING-FREQUENCY GUIDING FILTERS
(1995-09-15)
DUNG, JC
;
CHI, S
;
WEN, SF
;
光電工程研究所
;
Institute of EO Enginerring
Reductions of the soliton interactions and jitter by the upsliding-frequency filter, the downsliding-frequency filter, and the zigzag-sliding-frequency filter are numerically studied. It is shown that the most effective filter for reducing the soliton interactions is the zigzag-sliding-frequency filter. (C) 1995 Optical Society of America
REDUCTION OF THE SOLITON INTERACTION AND THE GORDON-HAUS EFFECT BY OPTICAL-PHASE CONJUGATION
(1995-05-01)
WEN, SF
;
CHI, S
;
光電工程學系
;
Department of Photonics
The reduction of soliton interaction and the Gordon-Haus effect by optical phase conjugation is studied. The criteria for applying the conjugators are considered. It is shown that soliton transmission can be significantly improved by optical phase conjugation.
STUDY OF A LIGHTWAVE SYSTEM CONSISTING ENTIRELY OF ERBIUM-DOPED FIBER
(1993-08-01)
WEN, SF
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CHI, S
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光電工程學系
;
電信研究中心
;
Department of Photonics
Investigated is the distributed erbium-doped fiber amplifier of zero dB gain, which has the least required pump power by optimizing the doping density. The total pump power and signal-to-noise ratio of the periodically pumped transmission systems with the unidirectional and bidirectional pumps are obtained.
THE MAXIMUM BIT RATES OF SOLITON COMMUNICATION-SYSTEMS WITH LUMPED AMPLIFIERS AND FILTERS IN DIFFERENT DISTANCES
(1995-06-01)
CHI, S
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DUNG, JC
;
WEN, SF
;
光電工程學系
;
電信研究中心
The maximum bit rate of a soliton communication system with lumped amplifiers and optical filters is considered, When the dispersion of the fiber varies from one amplifier spacing to another amplifier spacing, the maximum bit rate is significantly reduced. To overcome the effect, the amplitude of the soliton is amplified so that it is still the average soliton corresponding to the fiber dispersion for an amplifier spacing, Thus, the maximum bit rate is only slightly less than that without the dispersion variations, For a given distance, the maximum bit rate limited by the stability and soliton interaction is obtained, The result is compared with that limited by the Gordon-Haus effect, For shorter transmission distance, the maximum bit rate is limited by the stability and soliton interaction, For longer transmission distance, the maximum bit rate is limited by the Gordon-Haus effect.
THE OPTICAL SOLITON TRANSMISSION AMPLIFIED BY BIDIRECTIONAL RAMAN PUMPS WITH NONCONSTANT DEPLETION
(1991-08-01)
WEN, SF
;
WANG, TY
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CHI, S
;
光電工程學系
;
電信研究中心
A numerical method is proposed to solve the coupled equations between the soliton and bidirectional Raman pump waves. The pump depletion due to the soliton is obtained without using the constant depletion approximation. With this method, the soliton propagation in a Raman-pumped fiber can be solved accurately. It is found that the constant depletion approximation is valid at a small depletion rate, which requires low soliton power (or long pulsewidth), small material loss, and a short-pump period. In a periodically Raman-pumped fiber, there exists a stable signal energy, which is very sensitive to the pump intensity. We have also studied the stability of the soliton propagation with nonconstant pump depletion. It is found that the stability predicted by nonconstant depletion (NCD) and constant depletion assumption (CDA) are generally different.
THEORY OF SELF-INDUCED TRANSPARENCY IN A KERR HOST MEDIUM BEYOND THE SLOWLY-VARYING-ENVELOPE APPROXIMATION
(1993-04-01)
CHI, SE
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WANG, TY
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WEN, SF
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電信研究中心
;
光電工程研究所
The self-induced transparency in the Kerr host medium has been studied beyond the slowly-varying-envelope approximation. An analytic solution is obtained. There exists a hyperbolic-secant soliton whose power, pulse width, group velocity, and propagation constant are uniquely determined for given parameters of the medium. The reductions of the group velocities of the solitons by the self-induced-transparency effect in the resonant medium with homogeneous and inhomogeneous broadening are also studied. It is found that there is negative dispersion induced by the self-induced transparency, which is not predicted by the theory with the slowly-varying-envelope approximation. The amount of the induced dispersion is determined by the total dispersion of the system required to be compensated by the Kerr effect. Numerical examples of the self-induced transparency in an erbium-doped fiber are shown. In a typical erbium-doped fiber, the soliton solution has not been found because the inhomogeneous-broadening linewidth of the medium is too large.
ULTRASHORT SOLITON PULSE-TRAIN PROPAGATION IN ERBIUM-DOPED FIBER AMPLIFIERS
(1994-09-15)
CHI, S
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CHANG, CW
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WEN, SF
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光電工程學系
;
Department of Photonics
A theoretical model for the transmission of ultrashort soliton pulse trains in erbium-doped fiber amplifiers is developed. The model is used to study nonreciprocal characteristics of energy amplification and the evolution of the pulse train in a doped fiber with different pumping configurations.