Tan Liying, Li Mengnan, Yang Qingbo, Ma Jing
Appl Opt. 2015 Mar 20;54(9):2318-25. doi: 10.1364/AO.54.002318.
In practice, due to the laser device and the inevitable error of the processing technique, the laser source emitted from the communication terminal is partially coherent, and is represented as a Gaussian Schell model (GSM). The cross-spectral density function based on the Gaussian model in previous research is replaced by the GSM. Thus the fiber-coupling efficiency equation of the GSM laser source through atmospheric turbulence is deduced. The GSM equation presents the effect of the source coherent parameter ζ on the fiber-coupling efficiency, which was not included previously. The effects of the source coherent parameter ζ on the spatial coherent radius and the fiber-coupling efficiency through atmospheric turbulence are numerically simulated and analyzed. The result manifests that the fiber-coupling efficiency invariably degrades with increasing ζ. The work in this paper is aimed to improve the redundancy design of fiber-coupling receiver systems by analyzing the fiber-coupling efficiency with the source coherent parameters.
在实际应用中，由于激光设备以及加工技术不可避免的误差，通信终端发射的激光源具有部分相干性，并表示为高斯谢尔模型（GSM）。以往研究中基于高斯模型的交叉谱密度函数被GSM所取代。由此推导了GSM激光源通过大气湍流的光纤耦合效率方程。该GSM方程呈现了源相干参数ζ对光纤耦合效率的影响，这是之前未涉及的。通过数值模拟和分析了源相干参数ζ对空间相干半径以及通过大气湍流的光纤耦合效率的影响。结果表明，光纤耦合效率总是随着ζ的增加而降低。本文的工作旨在通过分析具有源相干参数的光纤耦合效率来改进光纤耦合接收器系统的冗余设计。
