相关实验视频
Updated: Jan 17, 2026

06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
9.6K
概括
我们开发了一种新的方法,用于使用双路结构的高灭绝比 (ER) M-ary脉冲位置调制 (M-PPM) 信号. 这种技术显著提高了光通信系统的信号质量.
科学领域:
- 光学通信是指光学通信.
- 信号处理 信号处理
- 调制技术 调制技术
背景情况:
- 高灭绝比 (ERs) 对于高效的光通信至关重要.
- 现有的M-ary脉冲位置调制 (M-PPM) 方法在实现更高的ER方面存在局限性.
- 马赫-泽恩德调制器 (MZM) 是光学调制中的关键组件,但可以具有有限的ER.
研究的目的:
- 提出和演示一种用于产生具有高灭绝比率 (ERs) 的M-ary脉冲位置调制 (M-PPM) 信号的新方法.
- 通过改进信号调制来提高光通信系统的性能.
- 为了克服基于MZM的标准调制的ER限制.
主要方法:
- 使用双路结构,其中一个路径包含数据驱动的马赫-泽恩德调制器 (MZM),另一个路径包含相变器.
- 将两条路径与相对π相位转移重组,以增强所得到的ER.
- 使用商用相位和方位 (IQ) 调制器实现了该结构,以产生100Mb/s的256-PPM信号.
主要成果:
- 对于生成的256-PPM信号,实现了超过40dB的动态灭比 (ER).
- 演示了每位4.49光子 (PPB) 的接收器灵敏度,比特误差率 (BER) 为10-3.
- 获得的灵敏度仅比光学预放大256PPM信号的理论极限高2.33dB.
结论:
- 拟议的双路径方法有效地产生具有高ER的M-PPM信号,超过嵌入式MZM的性能.
- 该技术可显著提高接收器的灵敏度,接近理论极限.
- 这一进步对下一代高速和高性能光通信系统具有前景.
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