Zhaoxin Wang

A novel centrally controlled protection scheme for traffic restoration in WDM passive optical networks

We propose and experimentally demonstrate a novel centrally controlled protection scheme for arrayed waveguide grating-based bidirectional wavelength-division-multiplexing passive optical networks which can provide automatic traffic restoration against fiber cut between remote node and optical network unit. Compared with the previous structures, its requirements on the network resources are greatly reduced with negligible protection performance degradation.

A novel star-ring protection architecture scheme for WDM passive optical access networks

We propose and demonstrate a star-ring network architecture and wavelength assignment scheme for multi-wavelength passive optical networks with full path protection capability. Bi-directional traffic can be restored promptly for single/multiple link failure scenarios.

A single-fiber bi-directional WDM self-healing ring network with bi-directional OADM for metro-access applications

We propose and demonstrate a single-fiber bidirectional wavelength division multiplexing self-healing ring network for metro-access applications. By incorporating a simple bi-directional optical add-drop multiplexer at each network node as well as employing our proposed alternate-path switching scheme, the bi-directional traffic can be restored promptly under single fiber failure in the ring network. All the protection switching is performed at the hub only, thus the operation, administration and management cost can be easily optimized

Demonstration of a single-fiber self-healing CWDM metro access ring network with unidirectional OADM

A simple and effective coarse wavelength-division-multiplexing metro access network architecture with unidirectional optical add-drop multiplexer (OADM) for automatic optical protection in a hub/access-node single-fiber ring is proposed and experimentally demonstrated. This physical-ring/logical-star architecture greatly simplifies the design compared with previous works requiring bidirectional OADM.

A novel approach for clock recovery without pattern effect from degraded signal

Abstract A novel clock recovery scheme using two-ring injection mode-locked fiber ring laser based on all 10 GHz bandwidth components was demonstrated. With this scheme, the clock with low timing jitter was obtained from a degraded 10 Gb/s optical data stream. Optical clock recovery was also achieved from a degraded 20 Gb/s optical data train when the clock division technique in the opto-electronic oscillator (OEO) and the rational harmonic mode-locking technique in the fiber ring laser were applied. No pattern effect was observed in the experiments.

Combination of comb-like filter and SOA for preprocessing to reduce the pattern effect in the clock recovery

A comb-like filter and a semiconductor optical amplifier (SOA) were combined to preprocess the data signals before clock recovery utilizing injection mode-locked laser based on SOA. The amplitude fluctuation and timing jitters caused by the pattern effect in clock pulses were greatly reduced experimentally with this technology. Furthermore, it also demonstrated that clock could be recovered from the very degraded signals.

Polarization-Insensitive Widely Tunable Wavelength Conversion Based on Four-Wave Mixing Using Dispersion-Flattened High-Nonlinearity Photonic Crystal Fiber with Residual Birefringence

We demonstrate a simple polarization-insensitive scheme in a FWM-based wavelength converter using only a short span of high-nonlinearity dispersion-flattened PCF with residual birefringence with over 32 nm of tuning and 0.9-dB polarization sensitivity.

Experimental demonstration of a novel all-optical multilevel 4-amplitude-shifted-keying coding/decoding scheme

We demonstrated for the first time an all-optical multilevel 4-amplitude-shifted-keying coding and decoding technique, which encodes two on-off-keying signals into a 4-ASK signal using cross absorption modulation in an electro-absorption modulator and employs fiber-based all-optical approach to facilitate data detection.

Wavelength-tunable dispersion-imbalanced loop mirror based on dispersion-flattened high-nonlinearity photonic crystal fiber and its application in suppression of the incoherent interferometric crosstalk

Wavelength-tunable nonlinear suppression of incoherent interferometric crosstalk has been experimentally demonstrated using the dispersion-imbalanced loop mirror based on a 64-m-long dispersion-flattened high-nonlinearity photonic crystal fiber. The signal quality improvement is achieved over a wavelength range of more than 25 nm (1545-1570 nm).

Nonlinear Suppression of Incoherent Interferometric Crosstalk with Dispersion Imbalanced Loop Mirror using Dispersion-Flattened High-Nonlinearity Photonic Crystal Fiber

Nonlinear suppression of incoherent interferometric crosstalk has been experimentally demonstrated with dispersion imbalanced loop mirror using the dispersion-flattened high-nonlinearity photonic crystal fiber. The signal quality improvement is achieved over a wide wavelength range