Maximum fiber coupling efficiency and optimum beam size in the presence of random angular jitter for free-space laser systems and their applications.
Maximum fiber coupling efficiency and optimum beam size in the presence of random angular jitter for free-space laser systems and their applications.
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DOI：
10.1364/josaa.23.002246
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发表时间：
2006-09
期刊：
影响因子：
--
通讯作者：
M. Toyoshima
中科院分区：
文献类型：
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作者：
M. Toyoshima
自由空间激光通信系统使用基于光纤的技术，如光学放大器、接收器和高速调制器。在这些使用单模光纤的系统中，光纤耦合效率是需要解决的最重要的问题之一。对于光纤耦合光学系统，讨论了随机角抖动情况下聚焦光束与光纤模场大小之间的最佳关系。用模场半径归一化的最佳艾里盘半径作为随机角抖动的函数，对最大光纤耦合效率进行了解析推导。研究了光纤耦合信号在期望衰落概率下的衰落电平。结果表明，当最佳选择艾里盘尺寸时，模场半径归一化的随机角抖动大于约0.3时，平均误码率显著降低。
Free-space laser communication systems use optical-fiber-based technology such as optical amplifiers, receivers, and high-speed modulators. In these systems using single-mode fibers, the fiber coupling efficiency is one of the most significant issues to be solved. Optimum relationships between a focused optical beam and mode field size of the optical fiber in the presence of random angular jitter are discussed in relation to fiber-coupled optical systems. Maximum fiber coupling efficiency is analytically derived with the optimum Airy disk radius normalized by the mode field radius as a function of random angular jitter. The fade level of fiber-coupled signals at desired fade probability is investigated. It is shown that the average bit error ratio significantly degrades with the random angular jitter normalized by the mode field radius larger than about 0.3 when the Airy disk size is optimally selected.