Study in variable duty cycle return to zero pulse with multiplexed channels for SMFs

Abstract

In this paper analysis has been done with varying return-to-zero (RZ) pulsed duty cycle, differential phase shift keying 640Gbps (16x40Gb/s) multiplexed channel optical transmission system using different SMFs viz standard Single mode fiber (SSMF), Non Zero Dispersion shifted fibers (normal NZDSF and anomalous NZDSF fiber), Corning SMF.Optical transmission used for sixteen users operates at 40Gbps per channel, 0.20nm spaced sixteen channels and fiber span analysis is done for test length of 200km. We tested system for detailed performance study for its behavior with different duty cycles for optical RZ pulse, results showing lowest bit error rate for 0.80 duty cycles among selection of 0.5, 0.8.0.99 for four types of SMFs tested for optical communication. Single repeater less mode fiber length is increased from 60km at duty cycle 0.5 to NZDSF fiber length of 140km at duty cycle 0.99.Results are also compared through 10dB Q improvement and corresponding improvement in average eye opening pattern. NZDSF fiber shows much improvement in average eye opening diagram for 0.99 duty cycle compared to other fibers tested and other duty cycles tested.

Key words: DWDM, ASE, RZ, DPSK, OSNR.