Direct Detection of 107-Gb/s Polarization-Multiplexed RZ-DQPSK Without Optical Polarization Demultiplexing

We demonstrate a direct detection scheme for a 107-Gb/s polarization-multiplexed return-to-zero differential quadrature phase-shift keyed signal, featuring automatic polarization demultiplexing without polarization tracking. The technique is used to study the performance under various impairments, including tight optical filtering, polarization-mode dispersion, and single-channel transmission in a dispersion-managed optical link. The performance is also compared with optical polarization demultiplexing.