Electro-optic delay oscillators: intensity and phase modulation dynamics and synchronization

Optical chaos encrypted communication requires strong chaotic carrier in order to ensure the secrecy of the message. For the specific case of the electro-optic devices, the gain loop parameter is turned to obtain chaotic regime and further chaos is still welcome for encryption. Unfortunately, this gain loop is limited because of the saturation of the components. Even though we succeed in hiding the message with the chaotic carrier, security should remain during the transmission (without compromising the real addressee for decryption) even in the face of eavesdroppers who are so capitalizing on the dramatic progress in technology. However, the message is sometimes impeded during the transmission owing of either the interference or the lack of synchronization due to the fiber effects. Taking these points as the motivations, we propose an alternative way for chaos generation or chaos amplification using intensity modulation principle. Then we remedy the interference problem by exploring a phase modulation scheme in which an attention is also drawn to security by parameter mismatch numbers. Finally, we show the fiber effects for long distance chaos communication and we explore some existing correction ways to our scheme.