光纤混沌双向保密通信系统研究

Studies on Optical Fiber Bi-Directional Chaos Secure Communication Systems

本文提出光纤混沌双向保密通信设想 ,通过耦合光注入半导体激光器激光混沌全光耦合反馈同步系统和光纤传输信道 ,建立了光纤混沌双向通信系统模型 ,数值实现了该系统在长距离光纤传输中的同步 ,详细地分析了系统同步时间随光纤传输长度的关系 .证明了光纤的交叉相位调制是限制激光混沌在光纤传输中同步的主要原因 ,导出了系统传输的非线性相移 .数值模拟了具有正弦调制信号的调制频率 0 .5GHz混沌模拟通信和数字信号调制速率0 .4Gbit/s以及 2 0Gbit/s的混沌数字通信以及调制速率 0 .0 5Gbit/s混沌键控通信的应用 ,计算出光纤混沌数字通信速率和同步误差等关系 ,还特别分析了系统解码特性和调制带宽 ,表明系统具有非常好的保密性能和具有高速率通信的能力 .光纤混沌双向保密通信是可以实现的 .

An optical fiber bi-directional chaos secure communication system is proposed and a model of optical fiber bi-directional chaos communication is presented by coupling the all-light chaos coupling-feedback synchronous system with the injection-light semiconductor lasers and optical fiber channel. The synchronization is numerically achieved in long-haul optical fiber propagation and the system synchronous error is in detail analyzed. Chaotic laser synchronization is mainly limited by cross-phase modulation in the fiber and the propagation nonlinear phase shift is educed. Chaos analog secure communication with a sinusoidal modulation signal of 0.5 GHz, chaos digital secure communication with a digital modulation signal of 0.4 Gbit/s and 20 Gbit/s rates and chaos shift keying secure communication with rate 0.05 Gbit/s are numerically simulated, respectively. Relationship between the bit rate and the synchronous error is numerically calculated in optical fiber chaos digital secure communications. The decoding performance and the modulation bandwidth of the system are also analyzed in detail. The system shows the good abilities of robust security and high rate communications. So it could be realized for long-haul bi-directional optical fiber chaotic secure communications.