系统增益对光混沌通信系统性能影响的研究

针对强注入开环结构的外腔反馈半导体激光器混沌通信系统，数值计算得到系统增益与注入系数的定量关系曲线.对比是否使用系统增益对接收系统输出进行校正两种情况下系统的解调性能，表明使用增益校正的相减解调法获得的信息更接近原始信息.通过采用不同频率的正弦信号进行调制，表明信息频率对系统增益没有影响；用不同调制方法对0.2?Gbit/s数字信号加密，结果表明系统增益与信号类型及调制方法无关.关键词：光混沌通信强注入系统增益同步

Effect of system gain on optical chaotic communications systems

The chaotic communications systems with optical feedback lasers in strong injection and open-loop configuration are studied in this paper. The quantity relationship between gain and injection factor is obtained by numerical calculation. The demodulators performances under the conditions of whether the gain is used to adjust the output of the receiver are compared. The result indicates that the recovered message is more close to the original message by using the adjusted subtraction demodulation method. It is proved that message rate has no effect on gain by testing sine signals with different rates. Further，the gain is shown to be independent of message type and encryption mechanism by testing digital signals at 0.2?Gbit/s rate.
Keywords：optical chaotic communicationstrong Injectionsystem gainsynchronization