Wavelength Division Multiplexing between 2.5-Gbits/s Chaotic Optical Secure Channel and 10-Gbits/s Nonchaotic Fiber-Optic Channel

In this paper, we numerically investigate the wavelength division multiplexing (WDM) transmission between chaotic optical secure channel and nonchaotic fiber-optic channel. When the channel spacing is 0.8 nm, a 2.5-Gbits/s message masked by the chaotic optical secure channel and a 10-Gbits/s message carried by the nonchaotic fiber-optic channel can be achieved simultaneously. The results show that the Q-factor of the recovered message can be increased significantly when the launched power is reduced appropriately. The deterioration on the quality of communications caused by fiber dispersion can be compensated obviously when the symmetrical dispersion compensation scheme is adopted. In addition, the message is masked by chaos shift keying in the chaotic optical secure channel. The multiplexing distance between the chaotic optical secure channel and the nonchaotic fiber-optic channel is up to 150 km.