概括
长,随机扰乱的纤维中的模态分散 (MD) 统计数据与纤维长度无关. 高阶的MD效应在相似的光谱宽度上变得显著,模式频率变化占主导地位.
科学领域:
- 光纤通讯是指光纤通讯的一种方式.
- 在无序的媒体中波浪传播.
背景情况:
- 模态分散 (MD) 在多模纤维中显著影响信号完整性.
- 了解MD的统计性质对于设计高性能光学系统至关重要.
- 之前的研究往往侧重于低级的MD或理想化的纤维条件.
研究的目的:
- 在长,随机扰动的纤维中统计分析高达第三阶的模态分散 (MD).
- 调查MD统计数据对纤维长度 (L) 的依赖.
- 描述不同级别的MD和它们的频率依赖之间的相互作用.
主要方法:
- 一个随机扰乱的六模光纤的数值模拟.
- 分析群延迟矩阵及其频率导数.
- 概率密度函数的计算和规范化 (PDFs) 对1,2,3次数的 MD.
- 调查双变的联合PDF,以研究不同MD命令之间的相关性.
主要成果:
- 第一个,第二个和第三个顺序的概率密度函数 (PDF) 是独立于正常化后的纤维长度 (L).
- 第二和第三阶段的MD效应在可比的信号光谱宽度时变得显著.
- 主要模式的频率变化是第二次和第三次MD的主要因素.
结论:
- 纤维长度不会显著改变模态分散的规范化统计特性.
- 高阶模态分散效应与模态频率变化有很强的合,并受到这种变化的影响.
- 这些发现为管理先进光纤系统中信号扭曲提供了关键的见解.
相关概念视频
01:07What is a Mode?
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The mode is one of the commonly used measures of a central tendency. It is defined as the most frequent value in a data set.
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
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00:54Distribution and Dispersion
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To understand intra-specific interactions in populations, scientists measure the spatial arrangement of species individuals. This geographic arrangement is known as the species distribution or dispersion. Highly territorial species exhibit a uniform distribution pattern, in which individuals are spaced at relatively equal distances from one another. Species that are highly tied to particular resources, such as food or shelter, tend to concentrate around those resources, and thus exhibit a...
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01:10Polymers: Molecular Weight Distribution
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For any given polymer, the weight average molecular weight (Mw) is higher than, if not equal to, the number average molecular weight (Mn). The only situation in which the weight average molecular weight and the number average molecular weight are equal is when a polymer consists only of chains with equal molecular weight. However, this never happens in a synthetic polymer, since it is difficult to control the polymerization process up to a molecular level with accuracy to a hundred percent.
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01:06Skewness
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The longer the tail of the plot on one side, the more skewed it is. The skewness of a data set’s values suggests that the measures of central tendency...
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01:27Distribution of Molecular Speeds
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01:02¹H NMR: Interpreting Distorted and Overlapping Signals
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Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
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