Abstract Transmission–Reflection Analysis (TRA) is an inexpensive technique used in distributed monitoring systems for single perturbation tracking. However, TRA is limited to long distance applications ( ~ km), since it has poor spatial resolution ( ~ m) when combined to standard silica fibers. This paper proposes the use of a magnesium and erbium co-doped optical fiber in conjunction with the TRA technique. The goal is to improve spatial resolution and accuracy for detection of loss-inducing disturbances along the sensing fiber. Bending losses are induced at several points of the fiber spaced at 50 cm over a 5.4 m fiber length, where each curve is clearly identified with a maximum hysteresis of 1.65%. The localization of a strong disturbance with an estimated accuracy of ± 0.8 mm near the source end and ± 7.2 mm near the fiber end is analytically demonstrated. Regarding weak disturbances, the proposed approach is vulnerable to noisy measurements. However, the response accuracy has been estimated up to ± 36.7 mm.

中文翻译：

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高散射光纤中的传输-反射分析：与单模光纤的比较

摘要 传输-反射分析 (TRA) 是一种廉价的技术，用于分布式监测系统进行单扰动跟踪。然而，TRA 仅限于长距离应用（~km），因为当与标准石英光纤结合时，它的空间分辨率（~m）很差。本文建议将镁和铒共掺杂光纤与 TRA 技术结合使用。目标是提高空间分辨率和精度，以检测沿传感光纤的损耗诱导干扰。在 5.4 m 光纤长度上以 50 cm 间隔的光纤的几个点处引起弯曲损耗，其中每条曲线都清楚地标识为 1.65% 的最大滞后。强扰动的定位在源端附近的估计精度为 ± 0.8 mm 和 ± 7。分析证明了光纤端附近的 2 mm。关于弱干扰，所提出的方法容易受到噪声测量的影响。然而，响应精度估计高达 ± 36.7 mm。