Browsing by Author "Kao, MS"

Now showing 1 - 13 of 13

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 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 multi-level DWDM network using hybrid packet switching and wavelength routing
(2005)
Kuo, ST
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Kao, MS
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電信工程研究所
;
Institute of Communications Engineering
In this paper, a new approach for constructing a hierarchical DWDM network is proposed. It is comprised of multiple levels by using a special ring topology. On each network level, one or several ring structures, named as cells here, are employed. The multi-level DWDM network keeps the efficiency of packet-switched network and the simplicity of wavelength-routed network. We perform packet switching at some particular physical nodes on the bottom level. On all upper levels, wavelength routing is performed. As a result, the node configuration and network complexity can be simplified apparently. The performance analysis is provided to verify the feasibility of the proposed approach.
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 product-coded WDM coding system
(1996-01-01)
Kao, MS
;
Chen, HY
;
Lin, D
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電信工程研究所
;
電信研究中心
Forward error correction is a feasible approach to decline the bit error floor of lightwave systems, arising from the fact that a simple single-error-correcting code can reduce the error floor from O(P-e) to O(P-e(2)). Here we propose a novel wavelength demultiplexer (WDM) coding system using product code to improve performances of WDM systems with an error floor caused by fiber dispersion or system noises.
A reliable architecture for broad-band fiber-wireless access networks
(2003-02-01)
Lin, WP
;
Kao, MS
;
Chi, S
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電信工程研究所
;
光電工程學系
We propose a broad-band DWDN/SCM fiber-wireless access network based on a two-level bidirectional path-protected ring (BPR) architecture. This architecture can perform self-healing function under link failure. The proposed network can provide high reliability, excellent flexibility and large bandwidth for future broad-band wireless networks. Finally, we set up an experimental fiber-wireless network to demonstrate the feasibility of the proposed architecture.
A star-bus-ring architecture for DWDM/SCM passive optical networks
(2001)
Lin, WP
;
Kao, MS
;
Chi, S
;
光電工程學系
;
Department of Photonics
A high-capacity DWDM/SCM PONs based on a star-bus-ring architecture (SBRA) is proposed and experimentally verified. This architecture can provide high bandwidth, reliability and flexibility for future broadband service networks.
An all-optical network architecture
(1996-05-01)
Gipser, T
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Kao, MS
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電信工程研究所
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電信研究中心
;
Institute of Communications Engineering
A novel photonic network, MATRIX (for Multi-wavelength All-optical TRansparent Information eXchange), is proposed in this paper. The all-optical multihop network supports wavelength continuity and provides a very high network capacity. Spatial reuse of wavelengths as well as the multiplicity of fibers in optical fiber cables are exploited and enable the interconnection of N-2 network nodes with merely N wavelengths. The node structure is simple since neither tunable devices nor wavelength converters are required. Packets are routed through the network by photonic fast packet switching as well as by wavelength and experience a maximum hop number of two. Multiple optical paths between any pair of nodes provide a good network survivability.
Design and analysis of VCSEL based two-dimension wavelength converter
(2003-07-14)
Liu, H
;
Shum, P
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Kao, MS
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電信工程研究所
;
Institute of Communications Engineering
A novel two-dimensional vertical cavity surface emission laser (VCSEL) based wavelength converter is proposed. We developed a two-dimensional transmission line laser model (TLLM) to analyze the proposed wavelength converter. This model takes into account Bragg reflectors by using the modified connecting matrix. Therefore, accurate and efficient modeling of the VCSEL structure is achieved. Extinction ratio of the output signal is investigated by considering input signal power, wavelength, facet reflectivity and cavity diameter. (C) 2003 Optical Society of America.
Large-signal spurious-free dynamic range due to static and dynamic clipping in direct and external modulation systems
(1998-10-01)
Wang, BH
;
Chiang, PY
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Kao, MS
;
Way, WI
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電信工程研究所
Large-signal spurious-free dynamic range (SFDR) is useful in an optical system with a high intensity noise level, which can be due to optical reflections or optical beat interference, and with large modulating signals to achieve sufficient carrier-to-noise ratio (CNR). A closed-form analysis on large-signal SFDR due to static and dynamic clipping for direct and external modulation systems is presented in this paper. The analysis can be applied to laser diodes (LD's) and external modulators with arbitrary transfer functions. We have used the analysis to predict the theoretical upper-bound for large-signal SFDR due to static clipping in an ideal LD add external modulators with various linearization techniques. We have also used the analysis to predict the dynamic-clipping-induced nonlinear distortions (NLD's) id. a weakly clipped LD, and confirm that dynamic clipping is more important to consider than static clipping when weak LD clipping takes place. Large-signal SFDR's in practical LD's and external modulators were also compared. The validity of our analysis is confirmed through computer simulation and actual measurement of clipping-induced NLD's in a typical CATV-quality DFB LD.
Optical bypassing using a WDM-Gridconnect patchwork
(1997-07-01)
Jager, HA
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Kao, MS
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電信工程研究所
;
Institute of Communications Engineering
In this letter, the properties of transparent wavelength routed transport networks are analyzed which are based on a wavelength-divsion multiplexing (WDM)-Gridconnect patchwork and compared to networks built on a conventional fiber infrastructure. The patchwork represents an example of a partitioned wavelength routed fiber-optic transport network using optical bypassing. The cumulative transit traffic and path length statistics are calculated. Based on these results, recommendations for the transparent network partition size and the number of wavelengths are given.
The modified star-ring architecture for high-capacity subcarrier multiplexed passive optical networks
(2001-01-01)
Lin, WP
;
Kao, MS
;
Chi, S
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電信工程研究所
;
光電工程學系
A modified star-ring architecture (MSRA) consisting of a star network on the upper level and many concatenated ring subnets on the lower level is proposed for subcarrier multiplexed passive optical network (SCM-PON), The upper level star network ensures high network capacity and its weakness in reliability is overcome by the concatenated ring subnets with self-healing capabilities, The self-healing function can be performed at remote nodes (RNs) by using optical switches (OS) to reconfigure the ring subnets if any link fails, Moreover, we design the cascade add/drop transceiver (CAT) structure in the lower level ring subnets to completely eliminate the optical beat interference (OBI) problem and achieve an OBI-free optical network. Finally, we set up an experimental network to demonstrate the feasibility of this cost-effective survivable structure.
Theoretical study of extinction ratio and frequency chirping of VCSEL-based two-dimensional wavelength converter
(2004-02-01)
Liu, H
;
Shum, P
;
Kao, MS
;
電信工程研究所
;
Institute of Communications Engineering
A novel two-dimensional (2-D) vertical-cavity surface-emission laser (VCSEL)-based wavelength converter was reported, in which the VCSEL was used both as the laser source for the probe wave and as the semiconductor amplifier for performing cross-gain modulation. We have developed a complete 2-D transmission line laser model to analyze the proposed structure. The optimization of the wavelength location, input power level, as well as the reflectivity of the VCSEL facet have been done with respect to the, extinction ratio and peak chirp frequency.