Performance analysis of time-polarization multiplexed 40-Gb/s RZ-DPSK DWDM transmission

The performance of return-to-zero differential phase-shift-keyed dense wavelength-division-multiplexing transmission with time-polarization multiplexing or interleaving is investigated. Polarization interleaving enables further reduction of nonlinear penalties, especially in high-bit-rate transmissions where intrachannel nonlinear effects dominate. We show numerically that transmission distance can be much increased with this scheme in a 40-Gb/s system. Polarization scattering resulting from polarization-mode dispersion and cross-phase modulation is also much reduced as compared to that in on-off keying systems, making it possible for effective polarization demultiplexing that may also reduce system cost.