Li Juhao

Comparison of node architectures for elastic optical networks with waveband conversion

In Elastic Optical Networks (EONs) with flexible bandwidth allocation, the blocking probability is high because of spectral contention. Similar to the functionality of wavelength conversion in Wavelength-Division-Multiplexing (WDM) networks, waveband conversion has been proposed to solve spectral contention in EONs. In this paper, we discuss the design of node architectures for an EON with waveband conversion. Four node architectures with shared Tuneable Waveband Converters (TWBCs) are proposed, and their blocking performances are evaluated by simulation. Simulation results show that the blocking probability of a node is significantly improved by waveband conversion. The sharing efficiency of waveband converters is also investigated. Simulation results show that at the same blocking rate, the node architecture with converters shared per node can save more than 20% waveband converters compared with that of the one with converters shared per link.

Ultra-Long Haul L-Band WDM Transmission over a Standard Single-Mode Fibre Loop Using DCF+CFBG Hybrid Dispersion Compensation

We demonstrate a 10.7 Gb/s-line-rate L-band wavelength-division-multiplexer (WDM) loop transmission over a 1890-km standard single-mode fibre (SSMF) with a 100-km amplifier spacing as well as non-return-to-zero (NRZ) format. The dispersion compensating fibre (DCF) plus chirped fibre Bragg grating (CFBG) is employed for hybrid inline dispersion compensation. The power penalty of each channel is less than 3 dB after three-loop transmission. The experimental results show that high-performance CFBGs can be successfully used in ultra-long haul (>1000 km) WDM systems. We also point out that the all-CFBG compensation scheme is not suitable for re-circulating loop transmissions.

Experimental study of the transient power overshoot in backward-pumped Raman amplified WDM systems

The channel distribution of the transient power overshoots, caused by the channels adding up, in backward pumped Raman amplified wavelength division multiplexed systems is studied experimentally. It is found that the time for the output power of different signal to drop from the maximum values to the minimum values is not equal to each other. The shorter the signal wavelength is, the smaller the time is. And the shape of the channel distribution of the maximal value of the power overshoot in the output signal is similar to that of the system ON-OFF gain distribution.