概括
一个新的混合极化多样性方案有效地消除了光学频域反射计中的激光波长调整变化. 这种方法提高了极化稳定性,并实现了光纤设备的高灵敏度测量.
科学领域:
- 光电学是指光电子产品.
- 光纤光学是指光纤的使用.
- 计量学 计量学 计量学
背景情况:
- 光学反射计系统中的极化状态变化可能会降低测量精度.
- 激光器的波长调整引入了极化状态的不稳定性,影响了信号完整性.
- 现有的方法在很大波长调范围内努力抑制极化色.
研究的目的:
- 为光学频域反射计 (OFDR) 提出和验证一个新的混合极化多样性方案.
- 为了消除由激光波长调节引起的极化状态变化.
- 为了提高光纤传感中的测量灵敏度和空间分辨率.
主要方法:
- 实施混合偏振多样化方案,使用45°偏振器.
- 保持信号极化以减轻波动.
- 在10米光纤设置中测试灵敏度和分辨率.
主要成果:
- 实现了极化角度波动只有2.81°.
- 实现了-145dB的测量灵敏度,雷利散射信号与噪声比为32dB.
- 通过广泛的波长调范围 (1480 nm至1640 nm) 证明了极化色抑制.
- 实现了6微米的空间分辨率.
结论:
- 拟议的混合极化多样化方案有效地抑制了OFDR中的极化色.
- 该方案使光纤设备的高精度结构测量成为可能.
- 这种技术为先进的光纤应用提供了高空间分辨率和灵敏度.
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