Narrow Results

This paper presents a numerical analysis and comparison on the performance of multi-pump gain-flat Raman amplifiers based on triangular photonic crystal fiber and conventional fiber. It is demonstrated that the extra 5.93 dB Raman net gain can be achieved in the L-band when PCF acts as Raman gain medium. The noise performance of the two amplifiers are also calculated and compared. Comparison with the data of published literature was also carried out to verify our analysis. The results showed that PCF is the appropriate candidate for high gain Raman amplifiers.

The influence of pump direction in all-optical gain-clamped fiber Raman amplifier using the directional couplers in feedback loop is demonstrated. The isolator direction decided the lasing direction in feedback loop. The comparison of performance in two lasing directions for both schemes is shown. It is concluded that the forward pumping configuration with forward lasing has better gain clamping performance and noise performance.

In this paper, an ultra-long distance transmission fiber link based on bidirectional Raman amplifier is studied by theoretical simulation and experimental verification. The power evolution of pump and WDM signals in optical fiber in 355 km transmission link is simulated theoretically. The performance of the ultra-long distance system based on co-pump/counter-pump/bidirectional-pump Raman amplifier (CORA/CTRA/BiRA) are simulated. And the power budget is also predicted by simulation. The performance of 10*100 Gb/s signal transmission in 355 km fiber link based on bidirectional Raman amplifier are tested experimentally. The theoretical and experimental results are in good agreement.

A gain-clamped fiber Raman amplifier is proposed and builds up. The result shows that gain fluctuation will be champed to a lower level with the dynamic gain control. And the dynamic gain control method is also fit for the Raman amplifiers with multi-wavelength pump.

In this paper, the method of optimizing pump allocation has been presented for bidirectionally pumped Raman amplifiers, and coupling interaction, among pumps, signals, ASE and DRBS noises, has been simulated; By optimizing pumps' wavelength and optical power, gain and noise spectrums have got flat at the same time.