Hung-Chang Chien

Tunable S-band erbium-doped triple-ring laser with single-longitudinal-mode operation

We propose and demonstrate a tunable and stable single-longitudinal-mode (SLM) erbium fiber laser with a passive triple-ring cavity structure in S-band operation. The proposed laser is fundamentally structured by using three different lengths of ring cavities, which serve as the mode filters. When a mode-restricting intracavity fiber Fabry-Perot tunable filter (FFP-TF) is combined, the proposed resonator can guarantee a tunable and stable SLM laser oscillation. Moreover, the performances of the output power, wavelength stability, tuning range, and side-mode suppression ratio (SMSR) are studied.

A self-protected colorless WDM-PON with 2.5 Gb/s upstream signal based on RSOA

In this investigation, we propose and demonstrate a colorless wavelength division multiplexed passive optical network (WDM-PON) at 2.5 Gb/s using reflective semiconductor optical amplifier (RSOA)-based optical networking units (ONUs); together with a self-protected architecture against fiber fault. In the optical line terminal (OLT), we use an array of self-seeding Fabry-Perot laser diodes (FP-LDs) to provide single-longitudinal-mode (SLM) continuous wave (CW) optical sources for the external injection to the RSOA-based ONUs. The self-survivable function for protecting the fiber fault in the distributed fibers and the proposed network performance are investigated and discussed.

Single-Frequency Tunable Fiber Ring Laser Based on Erbium-Doped Waveguide Amplifier and Double Filters

We have proposed and experimentally demonstrated a single-longitudinal-mode tunable fiber ring laser based on an erbium-doped waveguide amplifier (EDWA) and two filters composed of a Fabry–Perot laser diode and a fiber Fabry–Perot filter. The side-mode suppression ratio (SMSR) of >32.6 dB/0.05 nm and the output power of >1.4 dBm over a wide tuning range from 1525.22 to 1565.45 nm in steps of 1.11 nm have been achieved for this ring laser. The power fluctuation of <0.1 dB and central wavelength variation of <0.01 nm also can be obtained.

Cost-Effective Colorless RSOA-Based WDM-PON with 2.5 Gbit/s Uplink Signal

We demonstrate a cost-effective FP-LD based CW injection light on OLT for colorless WDM-PON using RSOA-based ONU with 2.5 Gbit/s direct modulation upstream signal. The system performances of proposed colorless WDM-PON are also investigated.

Stable and tunable fiber double-ring laser based on an erbium-doped waveguide amplifier

A stable and tunable fiber double-ring laser based on an erbium-doped waveguide amplifier (EDWA) is proposed and experimentally demonstrated. A widely tunable range from 1527 to 1567 nm, the side-mode suppression ratio (SMSR) of >45.6 dB/0.05 nm and the output power of >1.04 dBm in the operating range from 1535 to 1565 nm can be achieved for this ring laser. By applying the double-ring configuration, the ring laser is stabilized. The central wavelength variation of <0.02 nm and the power fluctuation of <0.03 dBm can therefore be retrieved.

A novel supervisory scheme for OXC based on different time-delay recognition

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/spl times/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.

EDFA-free all-optical 2R regeneration using a compact self-seeded Fabry-Pe/spl acute/rot laser diode

This study presents an erbium-doped fiber amplifier (EDFA)-free all-optical 2R (reamplification and reshaping) regeneration scheme based on a compact self-seeded Fabry-Pe/spl acute/rot laser diode. The proposed 2R regenerator achieves a straight line transmission at 10 Gb/s over 76 km without either the EDFA or the external probe laser, both of which are traditionally required. Additionally, device characteristics such as data-rate transparency, input dynamic range, amplified gain, and 2R regeneration performance are investigated experimentally.

All-optical 2R regeneration based on a compact self-seeded fabry-Pe/spl acute/rot laser diode with an embedded fiber Bragg grating

A cost-effective method, based on the injection-locking technique of a compact self-seeded Fabry-Peacuterot laser diode with a 10-mm-long embedded fiber Bragg grating cavity, is proposed and experimentally compared with the two-mode injection-locked scheme for all-optical 2R regeneration at 10 Gb/s. Placing the presented all-optical 2R regenerator after a 50-km fiber significantly improves the transmission performance of a signal over 50- and 100-km fiber links. The power penalties at BER=10-9 are similar to those of the two-mode injection-locked scheme

A new optical-path supervisory scheme for OXC based on unique FSR recognition

A new supervisory scheme, based on unique FSR recognition, to monitor the optical-path connection for optical cross-connects is proposed. This cost-effective method can not only verify the actual routing situation but supervise all channels simultaneously.

All-optical 2R regenerator using a compact self-seeded Fabry-Pérot laser diode incorporated with a bidirectional EDFA for 10 Gb/s transmission system

A cost-effective all-optical 2R regenerator, comprising a compact self-seeded Fabry-Perot laser diode, and a bidirectional EDFA, is proposed. This module, with 10.2-dB gain, achieves 6.4-dB power-penalty improvement over the 1R regenerator in the 100-km transmission.