Linear and nonlinear performance of 42.7-Gb/s single-polarization RZ-DQPSK format

We experimentally examine the performance of a single-polarization 42.7-Gb/s return-to-zero differential quadrature phase-shift keying optical signal. We evaluate the penalties arising from chromatic dispersion, polarization-mode dispersion, narrowband optical filtering, and nonlinear transmission over standard single-mode fiber.