Photonic Sensors, 2015, 5 (3): 217, 网络出版: 2015-10-22
OFDR Based Distributed Temperature Sensor Using the Three-Channel Simultaneous Radio-Frequency Lock-In Technique
OFDR Based Distributed Temperature Sensor Using the Three-Channel Simultaneous Radio-Frequency Lock-In Technique
Distributed temperature sensor incoherent optical frequency domain reflectometry radio-frequency lock-in amplifier simultaneous detection
摘要
Abstract
Weak signal detection for single-mode fiber-optic distributed temperature sensor (DTS) is a key technology to achieve better performance. A hybrid technique combining the incoherent optical frequency domain reflectometry (IOFDR) and the three-channel simultaneous radio-frequency (RF) lock-in amplifier (LIA) is presented to improve the signal-to-noise ratio (SNR) of the measured spontaneous Raman backscattered light. The field programmable gate array (FPGA) based RF-LIA is designed with a novel and simple structure. The measurement frequency range is achieved from 1 kHz to 100 MHz. Experimental results show that the backscattered light signal of picowatt level can be detected with high SNR. With a 2.5 km single-mode fiber, a 1064 nm laser source, and the measurement time of 500 s, this sensing system can reach a spatial resolution of 0.93 m and a temperature resolution of about 0.2℃.
Ke CHEN, Xinlei ZHOU, Wei PENG, Qingxu YU. OFDR Based Distributed Temperature Sensor Using the Three-Channel Simultaneous Radio-Frequency Lock-In Technique[J]. Photonic Sensors, 2015, 5(3): 217. Ke CHEN, Xinlei ZHOU, Wei PENG, Qingxu YU. OFDR Based Distributed Temperature Sensor Using the Three-Channel Simultaneous Radio-Frequency Lock-In Technique[J]. Photonic Sensors, 2015, 5(3): 217.