A modified phase generation carrier technique for fiber-optic distributed disturbance sensor

作者：Lin Wentai^*; Lou Shuqin; Liang Sheng

来源：Optik, 2014, 125(3): 942-945.

DOI：10.1016/j.ijleo.2013.07.148

• Optical sensors
• Disturbance measurement
• Phase generation carrier
• Phase drift
• Location error

A modified phase generation carrier technique used in fiber-optic distributed disturbance sensor (FDDS) is proposed and investigated. The FDDS locates the disturbance by dual Mach-Zehnder (MZ) interferometers, however, the initializing phase error of the two MZ interferometer causes the location errors. For the modified PGC technique, a narrow band analog low pass filter is designed, which solves the problem of facilitating the digital narrow band low pass filter in high speed A/D acquisition. In addition, a special demodulation signal is proposed to demodulate higher-order harmonic, compensate the time delay of the long optical fiber and enhance the signal to noise ratio. It is found that the location errors caused by phase drift can be eliminated in our experiments.

• 出版日期2014
• 单位北京交通大学