概括
瓶束 (BVBs) 通过克服障碍物来改善自由空间光通信. 这种方法在动荡条件下增强了接收功率,超过了传统的轨道角动量 (OAM) 和贝塞尔束.
科学领域:
- 光学通信是指光学通信的应用.
- 波束物理学的光束物理.
- 自由空间光学 (FSO) 链接
背景情况:
- 带有轨道角动量 (OAM) 的束用于自由空间光学 (FSO) 通信,以绕过障碍物.
- 对OAM光束的应用受到接收器光圈大小要求的限制,这些要求必须与障碍物大小相适应.
- 传统的OAM光束在FSO链路中面临着由于大气流和接收器限制的挑战.
研究的目的:
- 提出一种用于产生具有抛物线轨迹的瓶状束 (BVBs) 的新方法.
- 为了评估BVB在大气流和有限的接收孔口下在自由空间传输性能.
- 调查BVBs在绕过FSO通信链路障碍方面的有效性.
主要方法:
- 通过操纵传统OAM光束的辐射相分布来生成BVB.
- 在不同的大气流强度 (D/r0=2) 和阻塞尺寸 (40毫米) 下模拟自由空间传输性能.
- 将BVB与使用有限接收孔径 (d=40 mm) 的传统OAM光束和贝塞尔光束进行比较.
主要成果:
- 与传统的OAM和贝塞尔束相比,BVB在OAM FSO通信链路中表现出更好的性能.
- 生成的BVB保持与预先设计的路径相容的轨迹.
- 在模拟条件下 (D/r0=2,40毫米阻塞),BVB实现了大约7dB和3dB的平均接收光学功率,相比传统的OAM和贝塞尔光束分别高出7dB和3dB.
结论:
- 拟议的方法有效地产生具有可控制的抛物线轨迹的BVB.
- 在FSO链接中,BVB表现出对大气流和阻碍物的优越稳定性.
- 基于OAM的FSO通信系统的可靠性和效率的提高,BVB是一个有前途的进步.
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