Performance comparison of 2.5Gbps FWM based DWDM system for enhanced number of users

FWM, one of the most feared elements in optical fiber communication has two detrimental effects on the system first being power depletion of the channel resulting in high bit error rate and second being interchannel crosstalks. Many methods have been devised to decrease the effect of FWM like use of NZ-DSF, RDF and spacing channels unequally. In this paper we have designed 1 user, 2 users, 4 users, and 8 users FWM based DWDM system for a bit rate of 2.5 Gbps. The designed system uses FWMpsilas property of generation of multiple wavelengths that can be used to serve the purpose of multiple laser inputs instead of actually using them. Performance parameters like BER, quality factor and received power of the above mentioned systems have been evaluated at variable distances i.e. 20 to 110 km of optical fiber cable. Results shows that for 1 user system BER varies from 1.60times10^-65 to 7.09times10^-49, for 2 users system BER varies from 5.36times10^-45 to 1.31times10^-29, for 4 users system BER varies from 7.60times10^-37 to 1.83times10^-25, and for 8 users system BER varies from 4.53times10^-29 to 4.40times10^-19. For 1 user system quality factor varies from 16.97136 to 14.54985, for 2 users system quality factor varies from 13.96861 to 11.16743, for 4 users system quality factor varies from 12.56121 to 10.28525, for 8 users system quality factor varies from 11.06188 to 8.75716. For 1 user system received power varies from - 0.854 dbm to -18.868 dbm, for 2 users system received power varies from -2.662 dbm to -20.662 dbm, for 4 users system received power varies from -5.827 dbm to -23.827 dbm, and for 8 users system received power varies from -9.086 dbm to -27.325 dbm. It can be concluded from the above discussion that as the number of users and distance of optical fiber increases, BER increases while quality factor and received power decreases.