title: Three-chip differential phase-shift keying maximum likelihood sequence estimation for chromatic-dispersion and polarization-mode-dispersion compensation.
abstract: We propose a novel three-chip differential phase-shift keying (DPSK) maximum likelihood sequence estimation (MLSE) for chromatic-dispersion (CD) and first-order polarization-mode-dispersion (PMD) compensation to extend the transmission reach of the DPSK signal. Such a technique searches the most probable path through the trellis for DPSK data sequence estimation by exploiting the phase difference between not only the adjacent optical bits but also the bits that are one bit slot apart. The proposed scheme significantly outperforms conventional two-chip DPSK MLSE in CD and PMD compensation. We show that the proposed three-chip DPSK MLSE can enhance the CD tolerance of 10 Gbit/s DPSK signal to 2.5 times of that by using two-chip DPSK MLSE and can bound the penalty for 100 ps differential group delay by 1.4 dB.
authors.affiliation: Department of Information Engineering, The Chinese University of Hong Kong, Shatin, China. jzhao2@ie.cuhk.edu.hk
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
authors.forename: Lian-Kuan
authors.initials: LK
authors.lastname: Chen