半导体激光器混沌双向保密通信系统理论研究

Theoretical Studies on Chaotic Semiconductor Laser Dual-directional Secure Communication System

提出外部光注入半导体激光器激光混沌全光耦合-反馈同步系统,进行激光器系统稳定性动力学分析并计算出最大Lyapunov指数,导出系统的同步误差扰动方程以及系统有混沌隐藏编码时的同步误差公式和解调公式,数值证明并模拟实现了系统的混沌同步,分析同步瞬态响应和噪声影响,该系统具有较强的抗干扰能力。模拟具有正弦调制信号的调制频率0.2 GHz混沌模拟通信和数字信号调制速率0.2 Gb/s的混沌数字通信以及调制速率0.05 Gb/s混沌键控通信的应用,特别分析了系统解码特性和调制带宽,系统无论是在时域还是在频域,都具有非常好的保密性,该系统可以作为混沌双向保密通信使用。研究表明系统准许在一定范围内可以有参数失配,系统的实际应用是有可能的。

A full-light chaotic synchronization system of external light injected semiconductor lasers with optical coupled-feedback is presented. The dynamical stable characterization of laser is analyzed, its maximum Lyapunov exponent is calculated. The system synchronous error perturbed equation is proved. Synchronous error and demodulation formulae are also theoretically demonstrated under chaotic masking encoding. And the system gradual synchronization is numerically certified and successfully simulated. Synchronization transient respond and noise effect also are analyzed. The system has an anti-disturbance ability. Chaotic analog secure communication with a sinusoidal signal of 0. 2 GHz modulation frequency, chaotic digital secure communication with a digital signal of 0. 2 Gb/s modulation rate and chaotic shift keying secure communication with a rate of 0. 05 Gb/s are numerically simulated, respectively. The decoding character and modulation bandwidth of the system are analyzed, in particular. The system shows the good ability of robust security in time-domain and frequency-domain, so it could be used in dual-directional chaotic secure communication. The system parameter mismatch is studied to illustrate that its practical performance can be realized because synchronization can be achieved under a certain range of parameter mismatch.