Browsing by Author "Chi, S"

Now showing 1 - 20 of 192

1.3 mu m quantum dot vertical-cavity surface-emitting laser with external light injection
(2005-10-27)
Peng, PC
;
Chang, YH
;
Kuo, HC
;
Tsai, WK
;
Lin, G
A 1.3 mu m quantum dot vertical-cavity surface-emitting laser (QD VCSEL) with external light injection is presented, having been experimentally demonstrated. The QD VCSEL is fabricated on GaAs substrate. The 3 dB frequency response of the QD VCSEL based on the TO-Can package is enhanced from the free-running 1.75 to 7.44 GHz with the light injection technique.
120-nm bandwidth erbium-doped fiber amplifier in parallel configuration
(2004-07-01)
Yeh, CH
;
Lee, CC
;
Chi, S
;
光電工程學系
;
Department of Photonics
A new S- to L-band erbium-doped fiber amplifier (EDFA) module, which reaches 120-nm gain bandwidth of 1480 to 1600 nm, has been experimentally investigated and demonstrated by using coupled structure. A 32.8-, 34.7-, and 38.1-dB peak gain is obtained at 1504, 1532, and 1568 nm, respectively, when the input signal power is -30 dBm. In addition, this proposed amplifier also provides a broad-band amplified spontaneous emission (ASE) light source of 1480-1606 nm with the output level above -40 dBm.
210-km Bidirectional transmission system with a novel four-port interleaver to facilitate unidirectional amplification
(2006-01-01)
Huang, MF
;
Chen, J
;
Feng, KM
;
Wei, CC
;
Lai, CY
A novel bidirectional transmission system is proposed and experimentally demonstrated using a four-port interleaver to enable unidirectional amplification. Following bidirectional transmission through 210 km of standard single-mode fibers, sensitivity variations of less than 0.2 dB, with a bit-error rate level of 10(-9) at 10 Gb/s, were observed between bidirectional and unidirectional transmissions.
A bidirectional 2 x 2 optical switch technique using absorption or amplification function of erbium-doped fiber
(2005-10-01)
Yeh, CH
;
Lee, CC
;
Chi, S
;
光電工程學系
;
Department of Photonics
A novel bidirectional 2 x 2 optical switch technique, based on conventional erbium-doped fibers (EDFs) that operate at a pumped or unpumped power level, is proposed and demonstrated experimentally. By using the amplification and absorption functions of EDFs and a simple architecture design, the input signals can be switched to a suitable port. The response time of wavelength switching approaches about 2 ms. Moreover, the behavior and system performance of the proposed configuration are also studied.
A broadband fiber ring laser technique with stable and tunable signal-frequency operation
(2005-07-11)
Yeh, CH
;
Chi, S
;
光電工程學系
;
Department of Photonics
A C- plus L-band fiber ring laser with wide wavelength tunability and single-longitudinal- mode oscillation is proposed and demonstrated experimentally. A saturable-absorber-based autotracking filter, consisted of an unpumped erbium-doped fiber (EDF) and an optical reflected mirror (ORM), is employed to provide fine mode restriction and guarantee the single-frequency operation. Output power of >2.1 dBm, power stability of <= 0.02 dB, wavelength variation of <= 0.01 nm and side-ode suppression ratio (SMSR) of >31 dB / 0.05 nm have been experimentally demonstrated for this single-frequency fiber laser over an operating range of 1550 to 1608 nm. (C) 2005 Optical Society of America.
A broadband fiber ring laser technique with stable and tunable signal-frequency operation: erratum (vol 13, pg 5240, 2005)
(2005-08-22)
Yeh, CH
;
Chi, S
;
光電工程學系
;
Department of Photonics
We present the corrected version of Fig. 4 below with the original caption. (c) 2005 Optical Society of America.
A cascade add/drop transceiver structure to solve the optical beat interference problem in subcarrier-multiplexed passive optical networks
(2000-04-05)
Lin, WP
;
Kao, MS
;
Chi, S
;
電信工程研究所
;
光電工程學系
A cascade add/drop transceiver (CAT) structure in a star-ring architecture for subcarrier-multiplexed passive optical networks (SCM-PONs) is demonstrated to overcome the optical beat interference (OBI) problem. The proposed CAT structure is a simple, reliable, and feasible approach for SCM-PONs. Our experimental results reveal that the CAT structure in a ring can completely eliminate the OBI problem, and maintain a good transmission quality. (C) 2000 John Wiley & Sons, Inc.
A cost-effective fast frequency-hopped code-division multiple-access light source using self-seeded Fabry-Perot laser with fiber Bragg grating array
(2004-11-01)
Peng, WR
;
Peng, PC
;
Lin, WP
;
Hsu, KC
;
Lai, YC
We propose a novel light source for the optical fast frequency-hopped code-division multiple-access scheme using a self-seeded gain-switched Fabry-Perot laser diode (FP-LD) with the reconfigurable fiber Bragg grating array (FBGA). The embedded FBGA in the external cavity loop encodes the input pulses both temporally and spectrally. Before feeding back into the FP-LD, the encoded optical pulses propagate the FBGA with reverse direction and are again temporally combined. With the corporation of the variable fiber delay line, the limitation of the pulse rate by the fixed external cavity length is removed and makes the scheme more flexible. The output with sidemode suppression ratio of more than 20 dB has been obtained. With three fiber Bragg gratings on the FBGA, we demonstrate the encoded chip rate of 1.425 GHz under the driving radio frequency of 475 MHz. It is proved that a different codeword can be generated by simply reconfiguring the encoder without changing the rest of the experimental setup.
A direct theory for the perturbed unstable nonlinear Schrodinger equation
(2000-05-01)
Huang, NN
;
Chi, S
;
Lou, BL
;
Chen, XJ
;
光電工程學系
A direct perturbation theory for the unstable nonlinear Schrodinger equation with perturbations is developed. The linearized operator is derived and the squared Jost functions are shown to be its eigenfunctions. Then the equation of linearized operator is transformed into an equivalent 4x4 matrix form with first order derivative in t and the eigenfunctions into a four-component row. Adjoint functions and the inner product are defined. Orthogonality relations of these functions are derived and the expansion of the unity in terms of the four-component eigenfunctions is implied. The effect of damping is discussed as an example. (C) 2000 American Institute of Physics. [S0022- 2488(00)00405-9].
A DWDM/SCM self-healing architecture for broad-band subscriber networks
(2003-02-01)
Lin, WP
;
Kao, MS
;
Chi, S
;
電信工程研究所
;
光電工程學系
A high-capacity dense wavelength-division multiplexing/subcarrier multiplexing (DWDM/SCM) network based on a self-healing star-bus-ring architecture (SBRA) is proposed and demonstrated. This architecture has a star subnet on the upper level to be a high-capacity infrastructure for the network, several bus subnets on the middle level to offer broad-band channels for multiwavelength signals, and many ring subnets on the lower level to serve a number of nodes. We design remote nodes and bidirectional wavelength add-drop multiplexers (WADMs) by using simple optical switches to reconfigure the network under link failure. We further employ M-quadrature amplitude modulation (M-QAM) and frequency shift-keyed (FSK) signals for downstream and upstream channels, respectively. The SBRA ensures an optical-beat-interference-free (OBI-free) and high-reliability optical network. Finally, we set up an experimental network to demonstrate the feasibility of the proposed architecture.
A gain-clamped S-band erbium-doped fiber amplifier using fiber Bragg grating
(2006-05-15)
Yeh, CH
;
Lin, MC
;
Chi, S
;
光電工程學系
;
Department of Photonics
We propose and investigate experimentally a gain-clamped S-band erbium-doped fiber amplifier module, employing a fiber Bragg grating to serve as a reflected element to lase a saturated tone injected into the module, by forward optical feedback method. In addition, different injected powers of the saturated tone are used to realize the performances of gain and noise figure for the proposed amplifier over the effectively wavelength range of 1478-1520 nm. (C) 2005 Elsevier B.V. All rights reserved.
A hybrid star-ring architecture for fiber Bragg grating sensor system
(2003-09-01)
Peng, PC
;
Tseng, HY
;
Chi, S
;
光電工程學系
;
Department of Photonics
In this letter, we present a hybrid star-ring architecture for a highly reliable fiber Bragg grating (FBG) sensor system and demonstrate its effectiveness. The main trunk of the proposed sensor network is star topology and the sensing branches comprise a series of concatenated ring subnets. The weakness in reliability of the star network is overcome by the ring subnets with a self-healing function based on the reconfigurable optical switches between each subnet. To enhance the signal-to-noise ratio (SNR) of the sensor system, we adopt a linear-cavity FBG laser scheme to construct our proposed hybrid star-ring architecture. Such a fiber-laser scheme results in the SNR over 48 dB for the sensor network. The network survivability of a ten-point FBG sensor is experimentally examined. It is shown that the proposed FBG sensor system can increase the reliability of a sensing network.
A new fiber-communication miniature sensor module
(2000)
Sheen, CS
;
Chi, S
;
光電工程學系
;
Department of Photonics
Sensing using multi-chip package for optical sensing device enjoys the benefits of both optics and integrated circuits. By including the advent of MEMS technologies it can potentially lead to a new generation of miniaturized optical sensing devices and system. We propose and fabricate a miniaturized radiation-sensing module, which transfer the output analog signal to a light signal and it can be easily delivered through a single mode fiber. It consists of an infrared sensing thermopile, an ASIC chip and a LED, which acts as an electric-optical signal transfer component. Details of these components design, fabrications, experimental results are presented in this paper.
A new process technique for complementary metal-oxide-semiconductor [CMOS] compatible sensors
(2001)
Sheen, CS
;
Chi, S
;
光電工程學系
;
Department of Photonics
A new sacrificial-etching-window (SEW) structure is reported for the first time, which can be used for most complementary metal-oxide-semiconductor (CMOS) compatible sensor structures. Using a buried sacrificial layer, the etching windows of the substrate can be extended beneath the membrane. The SEW technique combines the advantages of both surface micromachining by using a sacrificial layer structure and bulk micromachining by anisotropic etching of a silicon substrate. Using the SEW structure, one can speed up the etching rate and design a larger membrane with a larger active area. Several sensors are fabricated by 1.2 mum industrial CMOS IC technologies combined with subsequent anisotropic front-side etching stops. Three kinds of SEW thermoelectric sensors are reported in this paper, and the characteristics of the sensors are analyzed and measured.
A novel architecture for dense wavelength-division multiplexing/subcarrier multiplexing networks
(2002-01-05)
Lin, WP
;
Kao, MS
;
Chi, S
;
電信工程研究所
;
光電工程學系
We propose and demonstrate a new survivable dense wavelength-division multiplexing/subcarrier multiplexing (DWDM/SCM) network based oil the star-bus-ring architecture (SBRA). This architecture ensures an OBI-free optical network and can serve tremendous subscribers, In addition, remote nodes and bidirectional wavelength add/drop multiplexers (B-WADMs) are designed by, using simple optical switches to reconfigure the network under link failure. We further set up an experimental network to demonstrate the feasibility, of the proposed architecture. (C) 2001 John Wiley & Sons, Inc.
A novel dispersion slope compensator for the WDM transmission system
(1999)
Chi, S
;
Lin, SC
;
Dung, JC
;
光電工程學系
;
Department of Photonics
A new dispersion slope compensator by writing the Bragg gratings at different positions in a dispersion compensation fiber is proposed for the WDM transmission system to compensate for the accumulated dispersion of each channel.
A novel fiber-laser-based sensor network with self-healing function
(2003-02-01)
Peng, PC
;
Tseng, HY
;
Chi, S
;
光電工程學系
;
Department of Photonics
In this letter, we, present a novel fiber-laser-based sensor network. with self-healing. function and demonstrate its effectiveness. The network survivability and capacity for a multipoint sensor system ate enhanced by adding switches in a self-healing ring architecture. The fiber laser adopted in this system is a linear-cavity filter Bragg grating (FBG) laser leading to the signal-to-noise ratio. over 52 dB for the sensor network. The network survivability of a ten-point FBG sensor is experimentally examined. The experimental results show that the proposed system can facilitate reliable, sensing network for a large-scale and multipoint smart structure.
A novel scheme for better performance in optical code-division multiple access
(2005)
Peng, WR
;
Lin, WP
;
Chien, HC
;
Chi, S
;
交大名義發表
A new spectra-interleaved scheme for passive optical fast frequency-hopped code-division multiple access system is proposed. Interference and bit error rate are improved by numerical result with this new scheme.
A novel supervisory scheme for OXC based on different time-dilay recognition
(2005-12-01)
Lee, CC
;
Kao, TC
;
Chien, HC
;
Chi, S
;
光電工程學系
A novel supervising technique, based on different time-delay recognition scheme, for monitoring the switch fabric of optical cross-connects is proposed. This method features fast detection, high reliability, fault location, and actual routing information. The supervising of 4 x 4 switch fabric with a detecting time of less than 300 ns was achieved. It is also verified experimentally that the degradation of the system performance caused by this supervising approach is negligible.
A practical in-service supervisory technique using reflected-pulse detection based on OTDR for optically amplified passive branched CATV networks
(1999-05-01)
Lee, CC
;
Chi, S
;
光電工程學系
;
Department of Photonics
We propose and experimentally demonstrate an inservice supervisory tecchnique based on reflected-pulse detection, which can simultaneously monitor the performance of all active network devices (such as optical transmitter, optical amplifiers, and optical receivers) and locate the fiber fault in optically amplified passive branched cable TV networks by using a conventional optical time-domain reflectometer (OTDR) combined with 1 x 2 optical switches. The monitoring parameters such as required dynamic range of OTDR, response time, and the maximum number of element monitoring transponder are discussed.