DSP aided chromatic dispersion reckoning in single carrier high speed coherent optical communications

This paper demonstrates digital signal processing (DSP) based chromatic dispersion (CD) reckoning technique for single carrier high speed coherent optical communications. Coherent detection permits the optical field parameters (amplitude, phase and polarization) to be available in the electrical domain enabling new opportunity for multi-level signaling (M-ary PSK and M-ary QAM modulation), as well as the possibility of exploring polarization multiplexing. Again, it enables quasi-exact compensation of linear transmission impairments by a linear filter (equalizer), which can operate adaptively to overcome time-varying impairments. That is why Coherent detection employing QAM modulation formats has become one of the most promising technologies for next generation high speed transmission systems due to the high power and spectral efficiencies. With the development of DSP, coherent optical receivers allow the significant estimation of CD. In recent days, the realizations of these DSP algorithms for mitigating the chromatic dispersion in the coherent transmission systems are the most attractive investigations. In this paper, CD estimation technique has been improved using DSP algorithm and optimal OSNR, BER have been achieved.