Dispersion compensation for 10 Gb/s lightwave systems based on a semiconductor Mach-Zehnder modulator

For 10 Gb/s lightwave systems based on a semiconductor Mach-Zehnder modulator, the following dispersion compensating schemes are examined theoretically; asymmetry in the splitting ratio of the modulator input Y-branch waveguide, linear equalization using an analog delay line equalizer, dispersion compensating fiber, and direct prechirping for NRZ signals. It is shown that the combination of an asymmetric input Y-branch waveguide push-pull operation of the optical modulator, and dispersion compensating fiber offers the best dispersion limited transmission performance. With dispersion compensating fiber, a larger portion of the optical power is applied to the arm of the modulator with more absorption, whereas without dispersion compensating fiber. A larger portion of the optical power is applied to the arm of the modulator with less absorption.>