提出了采用双边缘技术测量光纤传感中的布里渊频移。利用边上信号对频率变化敏感的特点,提出了边缘检测技术,并通过设置最佳的工作点,使系统工作在最敏感的点上。理论分析表明,为实现0.5 MHz的布里渊频移测量精度,通过测量最大信号的常规检测所需的信噪比为65.1127 dB,单边缘检测所需的信噪比为37 dB,双边缘检测所需的信噪比为31 dB。所以,在相同信噪比下,与常规检测技术相比,边缘检测技术可以大大提高布里渊频移测量精度。

Measurement of Brillouin frequency shift distribution in fiber sensor based on double-edge technique is proposed. Utilizing the characteristic that the edge signal is sensitive to the change of frequency, edge detection technique is proposed, and the system is operated on the best sensitive point by setting the optimum point. From the theoretical analysis, in order to achieve Brillouin frequency shift accuracy of 0.5 MHz, the signal to noise ratio (SNR) required are 65.1127 dB, 37 dB and 31 dB for conventional detection by measuring the maximum signal, single-edge technique, and double-edge technique, respectively. So, for the same SNR, edge techniques can improve the measurement accuracy of Brillouin frequency shift greatly comparing with the conventional detection techniques.