We propose a possible improvement for optical hybrid transmission systems, based on 40G differential quadrature shift Keying (DQPSK) and 10G differential phase shift keying (DPSK) received by means of a Gaussian narrow filter. We report a reduced cross phase modulation (XPM), at the cost of a slightly more complex setup. This technique is especially effective for systems with low inline dispersion and offers similar performances on different types of fiber.
XPM reduction in hybrid 10G/40G transmission using 10-Gb/s narrow-filtered DPSK modulation / BERTOLINI M; SERENA P.; ROSSI N; BONONI A. - In: OPTICS EXPRESS. - ISSN 1094-4087. - 17:8(2009), pp. 5919-5924. [10.1364/OE.17.005919]