1.5μm CPFSK外差/差分—延迟解调实验系统

1.5μm Experimental System on CPFSK Heterodyne/Differential-Delay Demodulation

本文报道 1.5μm 连续相位 FSK(CPFSK)外差/差分-延迟解调相干光纤传输系统的初步实验结果.系统中,发送光源和本振光源分别采用自聚焦棒(GRINROD)外腔和光栅外腔半导体激光器,两者差拍得到的中频(IF)线宽约为2 MHz,采用中频跟踪环路,IF 稳定在810±0.5 MHz.用140 MHz 正弦信号对发送光源进行直接注入电流调制,调制信号经6.4 km 单模光纤传输后得到较高信噪比的解调信号.实验结果表明,CPFSK 方式适合于高码速率和频分复用(FDM)相干系统.

In this Paper,the Preliminary experimental results of 1.5μm Conti- nuous Phase FSK(CPFSK)heterodyne delay demodulation cohe(?)ent optical fiber transmission system are reported.In the system,the GRINROD and grating external cavity semiconductor lasers are used,(?)espectively,as tia(?)smitter and local oscillator.The beat linewidth between transmitter and local oscillator is about 2MHz.The Intermediate F(?)equency(IF)is stabilized at 810±0.5 MHz by an AFC.After tramsmitted through 6.4km single mode fiber,the 140MHz Sinusoidly modulated signal is (?)ec(?)ve(?)ed perfectly.The(?)esults show that the CPFSK is suitabe to high bit rate and Frequency-Divisicn-Multiplexing(FDM) coherent systems.