入射偏振态偏离TE模对光纤AM CATV外调制发射机性能影响的研究

Influence of the Incident Polarization State Drifting off TE Mode on Performance of the Optical Fiber AM CATV Externally Modulated Transmitter

从理论上分析了入射到调制器的偏振态偏离ＴＥ模时对外调制光发射机组合二次失真（ＣＳＯ）和组合三次差拍（ＣＴＢ）的影响。得出在ＴＥ，ＴＭ模插入损耗相同时，传输５９个ＰＡＬ－Ｄ频道，在保证ＣＳＯ＝－７０ｄＢｃ时，偏离ＴＥ模的角度应小于６°。

Influence of the incident polarization state drifting off TE mode on composite second order distortion (CSO) and composite triple beat distortion (CTB) of an optical fiber AM CATV externally modulated transmitter is analysed theoretically. The conclusion is that if the insertion losses of the TE mode and TM mode are same and 59 PAL D channels are transmitted, the deviation angle from the TE mode should be less than 6 degrees with CSO=-70 dBc. The result of a single channel transmission experiment is consistent with the theoretical analysis.