Abstract In many distributed Brillouin fiber-optic sensing systems, Stokes and anti-Stokes scattering have to be separated. Conventionally, optical filtering is adopted for the separation and inevitably incurs loss of the scattering signal due to the close frequency spacing between Stokes and anti-Stokes scattering. In this paper, a new technique to separate Stokes and anti-Stokes scattering is proposed based on optical coherent orthogonal receiving. With optical coherent orthogonal receiving, phase information of optical field can be preserved at detection and hence Stokes and anti-Stokes scattering can be arranged in coherent addition or cancellation through phase arrangement to realize the separation. Theoretical analysis of the principle is presented with confirmation by experiment results. Moreover, the technique does not include temperature sensitive component and hence shows good stability and robustness.

中文翻译：

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通过光学相干正交接收分离分布式布里渊传感器中的斯托克斯和反斯托克斯散射

摘要 在许多分布式布里渊光纤传感系统中，斯托克斯散射和反斯托克斯散射必须分开。传统上采用光学滤波进行分离，由于斯托克斯散射和反斯托克斯散射之间的频率间隔很近，不可避免地会导致散射信号的损失。本文提出了一种基于光学相干正交接收的分离斯托克斯和反斯托克斯散射的新技术。采用光学相干正交接收，可以在检测时保留光场的相位信息，因此可以通过相位排列将斯托克斯散射和反斯托克斯散射进行相干相加或相消排列，实现分离。对该原理进行了理论分析，并得到了实验结果的证实。而且，