光电振荡器产生宽带混沌光的时延特征分析

理论分析与数值研究了光电振荡器输出的混沌激光特性, 基于自相关分析方法, 详细研究了光电振荡器的直流偏置相移和反馈强度等工作参数对输出信号时延信息的影响. 数值研究表明: 增加反馈强度可以使时延信息变得更加微弱甚至消除; 相同条件下, 直流偏置相移对应的工作点越接近马赫-曾德尔调制器传输特性曲线的极值点, 时延信息越弱; 直流偏置相移为0时可以有效地抑制时延信息. 研究还发现, 当直流偏置相移和反馈调制产生的相移变化π/2时, 自相关曲线上对应于延迟时间处的相关系数符号发生变化. 关键词： 宽带混沌激光 延迟时间 光电振荡器

Analysis of delay time signature in broadband chaos generated by an optoelectronic oscillator

Chaotic laser characteristics of an optoelectronic oscillator are investigated theoretically and numerically, and the influences of the offset phase and the feedback strength on the time-delay signature of chaos which is generated by an optoelectronic oscillator are studied, based on the method of autocorrelation function. Numerical analyses show that the increase of the feedback strength can further suppress or even conceal the time-delay signature. The closer to the extreme point of the transmission curve the operating point corresponding to the DC offset phase, the weaker the time-delay signature is. The time-delay signature can be suppressed obviously as the offset phase is set to be 0. We also find that the sign of the correlation coefficient corresponding to the time-delay signature is changed when the offset phase and the phase shift caused by the delay feedback produce a phase-shift value of π/2.
Keywords： broadband chaotic laser delay time optoelectronic oscillator