Analysis of frequency chirping and extinction ratio of optical phase conjugate signals by four-wave mixing in SOA´s

We present a complete large-signal dynamic model of a wavelength converter or optical phase conjugator based on four-wave mixing in semiconductor optical amplifiers. The modified transfer matrix method (TMM) is used for implementing the large-signal dynamic model. It is possible for this model to involve not only forward traveling waves, but also backward traveling waves. Also, this model includes longitudinal variation of carrier-induced reflective index, α-parameter, gain, carrier density, photon density, reflection, and amplified spontaneous emission noise at each small section. Therefore, we can accurately evaluate frequency chirping, optical pulse pattern, and extinction ratio of the conjugate signal. Th eye-opening penalty has been calculated to investigate the effects of frequency chirping and extinction ratio on transmission performance