A new OTDR based on probe frequency multiplexing
Two signal multiplexing methods are proposed and experimentally demonstrated in optical time domain reflectometry(OTDR)for fault location of optical fiber transmission line to obtain high measurement efficiency.Probe signal multiplexing is individually obtained by phase modulation for generation of multi-frequency and time sequential frequency probe pulses.The backscattered Rayleigh light of the multiplexing probe signals is transferred to corresponding heterodyne intermediate frequency(IF)through heterodyning with the single frequency local oscillator(LO).Then the IFs are simultaneously acquired by use of a data acquisition card(DAQ)with sampling rate of 100Msps,and the obtained data are processed by digital band pass filtering(BPF),digital down conversion(DDC)and digital low pass filtering(BPF)procedure.For each probe frequency of the detected signals,the extraction of the time domain reflecting signal power is performed by parallel computing method.For a comprehensive performance comparison with conventional coherent OTDR on the probe frequency multiplexing methods,the potential for enhancement of dynamic range,spatial resolution and measurement time are analyzed and discussed.Experimental results show that by use of the probe frequency multiplexing method,the measurement efficiency of coherent OTDR can be enhanced by nearly 40 times.
Rayleigh scattering coherent OTDR probe frequency multiplexing parallel computing dynamic range spatial resolution coherent Rayleigh noise heterodyne detection noise level reduction measurement efficiency
Lidong Lu Yun Liang Binglin Li Jinghong Guo Xuping Zhang
China Electric Power Research Institute,8 Nanrui Road,Nanjing,China 210003 Institute of Optical Communication Engineering,Nanjing University,22 Hankou Road,Nanjing,China 21009
国际会议
2013 International Conference on Optical Instrument and Technology (OIT’2013)(2013年光学仪器与技术国际会议)
北京
英文
1-7
2013-11-17（万方平台首次上网日期，不代表论文的发表时间）