光纤CATV中调相法抑制相位干涉噪声的研究

Study on phase modulation for interferometric noise suppression in optical fiber CATV transmission system

本文从理论上研究了附加相位调制抑制相位干涉噪声的方法 ,研究表明 :在光纤AM CATV外调制传输系统中 ,对传输光载波信号引入附加相位调制 ,当相位调制信号的频率为CATV频带的两倍以上时 ,可以有效地抑制相位干涉噪声的发生 ,抑制程度与相位调制度有关。

Phase noise fluctuations in the output of a semiconductor laser can produce intensity noise fluctuations upon transmission through a fiber optic link due to interferometric phase to intensity conversion,and therefore badly decreases the performance of the optical communication system Theoretical study on phase modulation for interferometric noise suppression in optical fiber AM CATV externally modulated transmission system is presented in this paper It has been shown by our investigation that the interferometric phase noise can be suppressed effectively as long as the frequency of phase modulation signal is at least two times the highest frequency of CATV signal,and the suppression rate is dependence of the phase modulation index.