The proposed model is validated for Er/Yb co-doped amplifier and Raman amplifier separately by comparing the calculating results with the experimental data. Different pump powers are used for both EYDFA and RA with 1 μW input signal power, 1 m length of Er/Yb amplifier and 25 km length of Raman amplifier (RA). The glass fiber used for both Er/Yb and Raman amplifiers is phosphate. The initial energy transfer efficiency for Er/Yb co-doped fiber amplifier (EYDFA) is introduced, while the amplified spontaneous emission (ASE) is neglected. The calculations are performed under a uniform dopant and steady-state conditions. Gain and noise figure enhancement of Er+3/Yb+3 co-doped fiber/Raman hybrid amplifierĪn Er/Yb co-doped fiber/Raman hybrid amplifier (HA) is proposed and studied theoretically and analytically to improve the gain and noise figure of optical amplifiers. We are presenting the modeling and analysis of power transients and its control using a pump control method for a single and multi-pump scheme. Fast signal power transients in the surviving channels are caused by the cross-gain saturation effect in RFA and the slope of the gain saturation characteristics determines the steady-state surviving channel power excursion. Recently the analysis of RFAs dynamic response and transients control has become important in order to predict the system response to add/drop of channels or cable cuts in optical systems, and avoid impairments caused by the power transients. Raman fiber amplifiers (RFA) are being used in optical transmission communication systems in the recent years due to their advantages in comparison to erbium-doped fiber amplifiers (EDFA). Transients control in Raman fiber amplifiersįreitas, Marcio Givigi, Sidney N., Jr. A theoretical model of Raman fiber amplifier with multiple-clad fiber is developed, and numerical simulation proves that the proposed scheme can improve the conversion efficiency and brightness enhancement of cladding pumped Raman fiber laser. To overcome the problem, a cascaded-cladding-pumped cascaded Raman fiber laser with multiple-clad fiber as the Raman gain medium is proposed.
To get high conversion efficiency, the inner-cladding-to-core area ratio has to be less than about 8, which limits the brightness enhancement. The conversion efficiency of double-clad Raman fiber laser is limited by the cladding-to-core area ratio. Cascaded-cladding-pumped cascaded Raman fiber amplifier.