L.K. Chen

A novel bidirectional wavelength division multiplexed passive optical network with 1:1 protection

We propose a novel network architecture for WDM-PON which offers 1:1 protection capability. In case of any fiber cut between remote node and ONUs, the affected ONU can re-route the wavelength channels via the adjacent ONU.

Fundamental limitation and optimization on optical code conversion for WDM packet switching networks

Fundamental performance limitation originated from multi-access interference on a generic code converter for WDM packet switching networks is derived and analyzed. A closed-form optimal threshold value that yields the lowest code conversion error is also given.

Resources optimization of integration of separate optical networks

Multiple networks create redundancy in fibre resources. Merging of networks becomes a necessity. Simulation was made to evaluate options of interconnection. Through interconnections, fibre links can be eliminated. Required network resources are greatly reduced.

A distributed collision avoidance protocol using pilot tone-based carrier sense mechanism for passive optical networks

A distributed collision-avoidance scheme employing pilot-tone based carrier sensing mechanism is proposed for the upstream multiaccess in PONs. Simulation results show the proposed algorithm outperforms the conventional CSMA/CD scheme in terms of network throughput and delay.

On robustness of in-band polarization-assisted OSNR monitoring schemes against PMD

In this paper, we present a comprehensive study on the robustness of in-band OSNR monitoring schemes against PMD. We evaluated the performance of two in-band polarization-assisted OSNR monitoring techniques, namely, polarization-nulling and orthogonal delayed-homodyne method.

An optical-path supervisory scheme for optical cross-connects using pilot-tones

All-optical WDMA transport networks depend critically on the functioning of the optical cross-connects (OXCs) that are responsible for routing wavelength channels to their respective destinations. Failure of the optical switches in OXCs will route the channels to the wrong destinations, degrading the network performance. Fault detection in channel add-drop and routing is thus of vital significance. We propose an optical-path supervisory scheme for OXCs by imposing pilot tones onto input wavelength channels as channel identifications (IDs).

Demonstration of an add-drop network node with time slot access for high-speed WDMA dual bus/ring packet networks

Summary form only given. High-speed wavelength division multi-access (WDMA) ring and bus networks are very promising architectures to support multi-access of high-capacity data. Most WDMA networks are configured with fixed transmitter and tunable receiver (FTTR) and employ decentralized light sources. However, they require complicated control signaling and suffer from a wavelength matching problem. In this paper, we propose and demonstrate a practical WDMA ring/bus packet network node using tunable transmitter and fixed receiver (TTFR) configuration. Centralized light sources are used and time slot access is controlled by our proposed signaling scheme.

Optimization of microring-based optical interconnection configurations for the reduction of power consumption and insertion loss

With the objectives of reducing power consumption and average insertion loss, optimal configurations for optical interconnection are determined, leveraging the asymmetric behaviors at cross/bar states of microring switching element. Besides, a novel heuristic is proposed.

A novel FFT-based EDFA supervisory scheme for WDM transmission systems

We have proposed and demonstrated a novel EDFA (erbium-doped fiber amplifier) supervisory scheme for WDM transmission systems. The working status of multiple optical amplifiers can be monitored by analyzing the RF spectra of the common supervisory wavelength at the receiver end using a fast Fourier transform (FFT).

Polarization insensitive waveform restoration and channel crosstalk reduction in semiconductor optical amplifier gates using polarimetric filtering

We present a polarization-insensitive approach for waveform restoration in semiconductor-optical-amplifier (SOA) based optical gates using nonlinear polarization rotation in SOA and polarimetric filtering. The scheme is capable of suppressing the channel crosstalk owing to SOAs cross-gain-modulation for multiple input wavelengths.