概括
高级拉盖尔-高斯光束通过减少流效应来改善自由空间光学 (FSO) 通信. 与FSO系统中的传统高斯束相比,这些束提供了更好的性能和更低的功耗损失.
科学领域:
- 光学通信是指光学通信.
- 大气光学是大气光学.
- 波束物理学 波束物理学
背景情况:
- 自由空间光学 (FSO) 系统通常使用高斯波束,这些波束易受大气流的影响.
- 流会导致信号退化,限制FSO通信的性能和可靠性.
研究的目的:
- 调查在FSO系统中使用更高阶的拉盖尔-高斯 (Laguerre-Gaussian,LG) 束作为信号载体.
- 开发一种通用传输模型,用于LG光束在动荡的大气道中的传输.
主要方法:
- 开发了一种使用交汇超几何函数和修改的·卡尔曼流频谱的通用传输模型.
- 验证了对Huygens-Fresnel衍射的模型,功率误差为<0.9%,并实现了>10倍的计算速度.
- 进行了模拟和40Gbps正方位相位移键 (QPSK) FSO实验.
主要成果:
- 与高阶LG光束相比,高阶LG光束的光束扩散率降低,功率损耗较低,闪减轻,与高斯光束相比.
- 对于1×10-4的目标比特错误率 (BER),LG光束显著降低了所需的传输功率预算.
- LG01光束减少了1-1.5dB的功率预算,而LG10和LG02光束则减少了2-4dB.
结论:
- 高级LG光束在大气流下在FSO通信中提供了卓越的性能.
- 拟议的模型准确地预测了LG光束的传播和性能,验证了其实际适用性.
- LG光束是高斯光束的有希望的替代品,可以提高FSO系统的可靠性和效率.
相关概念视频
Distribution of Stresses in a Narrow Rectangular Beam
481
In studying beam stress distribution, examining an elemental section is essential. To determine the average shearing stress on this face, the calculated shear is divided by the surface area. Importantly, shearing stresses on the beam's transverse and horizontal planes mirror each other, indicating a consistent stress distribution along the upper region of the beam. Notably, shearing stresses are absent at the beam's upper and lower surfaces due to the absence of applied forces in these...
481
Elastic Curve from the Load Distribution
498
The structural behavior of beams under distributed loads is critical for engineering analysis, which focuses on predicting how beams bend and react under such conditions. Different types of beams (e.g., cantilever, supported, or overhanging) behave differently under distributed load conditions.
For all beams, the analysis of the beam's reaction to distributed loads begins by understanding the relationship between a beam's load and the resulting shear forces and bending moments. Initially, this...
For all beams, the analysis of the beam's reaction to distributed loads begins by understanding the relationship between a beam's load and the resulting shear forces and bending moments. Initially, this...
498
Shear on the Horizontal Face of a Beam Element
517
To understand shear on the flat side of a prismatic beam element, consider the vertical and horizontal shearing forces, and the normal forces, acting on the element. The element's upper (U) and lower (L) sections, which are divided by the beam's neutral axis, are examined. The equilibrium of these forces is determined by applying the equilibrium equation, which helps identify the horizontal shearing force. This force is directly related to the bending moments and the cross-section's...
517
Beams with Unsymmetric Loadings
409
Analyzing a supported beam under unsymmetrical loadings is essential in structural engineering to understand how beams respond to varied force distributions. This analysis involves calculating the deflection and identifying points where the slope of the beam is zero, which are crucial for ensuring structural stability and functionality.
The first moment-area theorem determines the slope at any point on the beam. This theorem indicates that the change in slope between two points on a beam...
The first moment-area theorem determines the slope at any point on the beam. This theorem indicates that the change in slope between two points on a beam...
409
Shearing Stresses in a Beam: Problem Solving
620
A cantilever beam with a rectangular cross-section under distributed and point loads experiences shearing stresses. The analysis begins by identifying the loads acting on the beam. Then, the reactions at the beam's fixed end are calculated using equilibrium equations. The vertical reaction is a combination of the distributed and point loads, while the moment reaction is the sum of their moments. The shear force distribution along the beam, resulting from these loads, is established by creating...
620
Beams with Symmetric Loadings
385
The moment-area method is an analytical tool used in structural engineering to determine the slope and deflection of beams under various loads. Consider a cantilever with a concentrated load and moment at the free end. The first step is constructing a free-body diagram to calculate the reactions at the fixed end. Next, the bending moment diagram is plotted to visualize how the bending moment varies along the beam's length, focusing on points where the bending moment equals zero.
The M/EI...
The M/EI...
385


