为抑制温度对基于光纤的频率传输系统稳定性的影响,建立了相应的物理模型,并进行了定量分析。结果表明,温度的缓慢变化不会影响频标信号的短期稳定性,但会使其长期稳定性变差。因此,在高稳定光纤频率传输系统中,必须通过相位补偿来有效地抑制温度引入的相位噪声。在此基础上进行了仿真研究和实验检测,仿真结果表明,通过该补偿技术可以在环路带宽内有效抑制光纤温度效应引入的相位噪声,环路的带宽由光纤传输距离决定。实验结果验证了理论分析的有效性。
The influence of ambient temperature change on the stability of the optical fiber based frequency transmission system is analyzed.The results show that the variation of temperature has no effect on the short-term stability of the transmitted standard frequency signal.The long-term frequency stability,however,will be degraded when the change of ambient temperature is relatively slow.As a result,in the ultrastable frequency transmission system based on optical fiber,it is necessary to suppress the phase noise induced by the temperature with a phase compensator.The performance of the optical phase compensator is studied theoretically and analyzed by simulation.The results show that the phase noise in the loop bandwidth can be effectively suppressed by the optical phase compensation method.Theoretical and simulation results are validated by experiment.