Some Studies on Gain Spectra Optimization of Multi Pumped Th3+ - Er3+ (Thulium Erbium) Doped Hybrid Optical Amplifier

In Optical fiber communication signal degradation occur hence we use Optical Amplifiers which have advantages over regenerators as it does not require to do any reshaping, retiming, retransmitting or any costly OE-O conversions. Limitation of Optical Amplifiers arises when non-linear effects occur. So, there is demand of optical amplifiers which provide better performance (in term of transient performance, gain flatness, larger gain bandwidth etc.) for DWDM systems. To minimize the impairments due to fiber nonlinearities and to enhance the gain bandwidth and/or gain flatnesshybrid optical amplifier is a promising technique for future DWDM multiterabit systems. In this paper many hybrid optical amplifications like EDFA, TDFA, FOPA, OPCPA, TDFAFOPA and TDFA-RAMAN are surveyed to carry work on TDFA-EDFA hybrid amplifier. Methods of implementing hybrid amplifiers and types of hybrid models that are available for use are surveyed. Comprehensive gain characteristics of TDFA, EDFA and hybrid amplifiers (TDFA-EDFA) connected in cascaded and parallel configurations are reported. TDFA and EDFA are simulated using multiple pumping scheme at variable lengths in order to optimise the gain spectra.