Improved Signal Demodulation Method in Optical Fiber Seismometer
Improved Signal Demodulation Method in Optical Fiber Seismometer
复制标题
光纤地震仪信号解调方法的改进
DOI：
10.1166/sl.2012.2453
复制
发表时间：
2012-07
期刊：
影响因子：
--
通讯作者：
Yuan, L.
中科院分区：
文献类型：
--
作者：
Yuan, Y.;Yang, J.;Zhou, A.;Yuan, L.
An improved phase generated carrier (PGC) demodulation method is proposed for signal demodulation of a Michelson interferometer based long arm optical fiber seismometer. The analysis is based on a semi-physical simulation system. The interference arms of the seismometer mode are set to be 1 km. By introducing an intermediate term into the traditional PGC-DCM (differential cross-multiplying), the interference light intensity fluctuation (B value fluctuation) can be removed in output signal of the seismometer and therefore the signal demodulation error can be reduced. The improve PGC method can overcome the disadvantage that traditional PGC-DCM demodulation method susceptible to interference light intensity (B value) fluctuation. The simulation results show that when the light intensity fluctuation rate as high as 98%, a total-harmonic-distortion (THD) of below 0.0046% and a signal-to-noise-and-distortion (SINAD) of 62 dB can be achieved. In addition, the frequency noise caused by the light intensity fluctuation also can be effectively reduced.
