A new scheme for cross-gain modulation (XGM) wavelength converter based on multi-electrode single-port-coupled semiconductor optical amplifier (SOA) is proposed, and a comprehensive broad-band dynamic model of this kind of wavelength converter is presented. By numerical simulation, the output performances of two kinds of XGM wavelength converter based on multi-electrode single-port-coupled SOA and based on single-port-coupled SOA are investigated. The result shows that the extinction ratio of XGM wavelength converter based on multi-electrode single-port-coupled SOA is greater than that of the later.