B. Cuenot

WDM signal regeneration using a single all-optical device

Using the principle of quasi-continuous filtering in a non-linear fibre, we propose an optical device for the simultaneous regeneration of sevaral channels at 40 Gbit/s. Simulations predict an improvement of the signal quality for four channels by more than 6.8 dB.

Recent developments in 40 Gsymbol/s coherent WDM

In this paper we investigate the non-linear transmission performance of 40 Gsymbol/s multi-carrier techniques, specifically Coherent WDM (CoWDM) for a variety of existing dispersion maps. Whilst the simulations on this paper were performed using NRZ OOK CoWDM implementation, the conclusions are also applicable to other multi-carrier techniques, such as OFDM.

1 b/s/Hz coherent WDM transmission over 112 km of dispersion managed optical fibre

The performance advantage of using dispersion-managed fibre in coherent WDM systems is demonstrated. Limitations due to nonlinearity are no more severe for a 298 Gb/s coherent WDM signal than for an individual 42.6 Gb/s channel.

Optical regeneration using self-phase modulation and quasi-continuous filtering

We propose a scheme for 2R optical regeneration based on self-phase modulation in fiber and quasi-continuous filtering. Numerical simulations demonstrate the possibility of increasing the transmission reach from 3500 to more than 6000 km at 10 Gb/s using 100-km spans. Spectral broadening is shown to be small using this technique, indicating its suitability for wavelength-division-multiplexing regeneration

Optical Regeneration of WDM Signals Using Quasi-Continuous Filtering

The design and performance of a novel all-fibre based 2R regenerator are presented. Simulations at 10 Gbit/s indicate Q-factor back-to-back improvements of 2.3 and 1.6 dB for single-channel and WDM operation respectively, which are the highest reported values. The transmission reach is increased from 3500 km to more than 6000 km at 10 Gbit/s. Towards practical realisation of this device, low-loss coupling between non-linear fibres is reported

Widely Tunable Modelocked Multiwavelength Ring Laser

Using parametric amplification in a highly nonlinear fibre, we demonstrate a widely tunable modelocked multiwavelength ring laser generating up to six simultaneous modes with 4.4 ps pulse width at 8.5 GHz repetition rate.

40 Gbit/s WDM all-optical regeneration using a fibre-based device

This paper presents the design of a 40 Gbit/s 4 channel multi-wavelength regenerator based on quasi continuous filtering. The quality factor improvement is estimated, as well as the distribution of the receiver voltage to characterize the regenerator.

Transmission Impairments for 298.2Gbit/s Coherent WDM over 600km of Standard Single Mode Fibre

Coherent wavelength division multiplexing (CoWDM) is a promising technique in order to achieve, in a simple and cost-effective configuration, high information spectral densities (ISD). This paper shows an estimation of the impact of non-linear effects (NLE) and polarisation mode dispersion (PMD) for a CoWDM system using standard single-mode fibre (SSMF), showing that this high ISD system offers similar total reach to a standard WDM system with 42.6Gbit/s NRZ channels. The impact of noise and NLE on a 298.2Gbit/s CoWDM system generated from seven 42.6Gbit/s random data streams (512 and 27-1 bits for simulated and experimental results respectively) was considered .

Modelocked Multiwavelength Ring Laser Using Parametric Amplification in Highly Non Linear Fibre

A modelocked multiwavelength ring laser is demonstrated showing up to six simultaneous propagating modes. The measured pulse width is 7 ps at a repetition rate of 9.4 GHz.

Tbit/s Optical Transmission Systems

We discuss our Science Foundation Ireland‐funded work to design of a highly spectral efficient Tbit/s optical transmission system for long‐haul communications. Such systems are comprised of several wavelength division multiplexing (WDM) channels (or frequency channels), closely spaced (<100 GHz), and modulated at high bit rates (40 Gbit/s). The highest efficiencies have been achieved using combinations of techniques, by increasing the information per channel and minimizing interferometric cross‐talk. In conventional systems, incoherent interference occurs when beat signals from adjacent channels fall within the receiver bandwidth. This generates noise if the relative phase is random, e.g., where independent lasers are used for each channel. However, if the optical phase difference between adjacent channels is controlled, the interference signal is deterministic. Therefore, if each channel is modulated with a data signal, any interference effect is distributed in the same way from one bit slot to another, ...