Vol.:(0123456789) Optical and Quantum Electronics (2019) 51:34 https://doi.org/10.1007/s11082-019-1743-x 1 3 Flat gain C + L band using optical amplifers for 200 × 14 Gbps DWDM system Ghanendra Kumar 1  · Sandeep Kumar 1 Received: 25 September 2018 / Accepted: 3 January 2019 / Published online: 9 January 2019 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract This paper has shown the analysis of 200 channels dense wavelength division multiplexing (DWDM) system with the data rate of 14 Gbps for attaining the fat gain for the channel spectrum from 1520 to 1640 nm. Analysis has also extended with the power amplifcation of erbium–ytterbium co-doped optical amplifer (EYBCDOWA) and Raman optical ampli- fer for the transmission distance of 120 km to mitigate the efect of crosstalk and bit error rate (BER). Final analysis has also recommended that this proposed system is capable to deliver the fat gain of 19.5 dB with minor variation of 0.95 dB to maintain the acceptable dense communication for long distance. Keywords EYBCDOWA · Raman optical amplifer · DWDM · BER · Crosstalk · Flat gain 1 Introduction Acceptable rating fattened gain is the main concern for dense wavelength division multi- plexing (DWDM) system to attain remarkable outcome to maintain the least fber losses for the betterment of optical communication. In this way optical amplifers are the main backbone for future dense communication process to control the efect of fber nonlinear- ity and play the main role to enhance the gain bandwidth for the support of fattened gain. Erbium–ytterbium co-doped optical amplifer (EYBCDOWA) has shown much attraction due to its high capacity bandwidth with the acceptable efect of gain (Kumar and Goyal 2018a; Mateo et al. 2008). With the comparison to erbium-doped fber optical amplifer (EDFOA), EYBCDOWA has been explored low noise power amplifcation and also shown best results in diferent power amplifcation (Radic et al. 2003; Kim et al. 2001). Sometime variations in gain are not acceptable due to mismatch in phase of the multiplexing signals. So to archive the acceptable gain, use of various techniques (use of dual pump power, fber Bragg grating, and attenuator) with other conventional optical amplifer have also used to maintain the power level of the optical pulse (Slavík et al. 2010; Dahan and Eisenstein 2005; Marhic et al. 2004; Kumar and Goyal 2018b; Hansryd et al. 2002). Unfortunately, * Ghanendra Kumar gkumar3c@gmail.com 1 Department of Electronics and Communication Engineering, National Institute of Technology, Delhi 110040, India