New Compensation Technique for Fiber Impairments in Ultra High Capacity Super channel Based on (QDPASK) Dense wavelength division multiplex (DWDM) systems


In this paper we want to increase the data rate and to get larger transmission distance, therefore we use the Advanced modulation technique QDPASK in DWDM system with low channels space. In case of long transmission distance and multi channels system both giving rise to inter channel crosstalk induced by fiber nonlinearities as a result the use of advanced modulation technique becomes difficult. In this paper Quaternary differential phase amplitude shift keying (QDPASK) is designed for 32 dense wavelength division multiplexing (DWDM) channels, therefore we proposed a new cascade compensation system consist of optical and digital back propagation techniques (ODBP) for compensate the linear and nonlinear effects . A performance of the system was reported using QDPASK DWDM fiber-optic system for various system parameters. The research is tested in VPI maker environment.