Realization of 16-channel digital PGC demodulator for fiber laser sensor array
This paper describes a 16-element DFB FL (distributed feedback fiber laser) sensor array system interrogated by Nl-PXI-based (PCI extensions for Instrumentation) digital PGC (phase generated carrier) technique. The lasing wavelengths of the DFB FLs are changed by the external strains or temperatures, and hence they can be used as sensors by detecting the wavelength shifts. An unbalanced MI (Michelson interferometer) is employed in the sensor array system to amplify the wavelength shifts of DFB FL sensors to detectable phase shifts. The output phase signals of the MI are separated into different channels by a DWDM, and then detected by a low-noise photodiode array. The digital PGC algorithm is realized on a PXI platform (NI, National Instruments), which consists of three FPGA (Field Programmable Gate Array) modules and a high performance system controller. The normalization of the interference fringe is proposed and realized in this paper to reduce the influence of the light intensity fluctuations, and a trigger mechanism is introduced into the digital multi-channel PGC demodulation scheme to synchronize the date among different channels. A 16-element DFB fiber laser sensor array system has been set up in the experiment and the demodulated results have demonstrated a minimum detectable wavelength shift of 1x10-6 pm/VHz, a linearity of as high as 0.9994, and a dynamic range of 110dB@100Hz.
Lin Wang Jun He Fang Li Yu-Liang Liu
Optoelectronics System Laboratory, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, P.R. China
国际会议
3rd International Photonics & OptoElectronics Meetings(第三届国际光子与光电子学会议 POEM 2010)
武汉
英文
1-6
2010-11-03（万方平台首次上网日期，不代表论文的发表时间）