概括
在自由空间光通信中的轨道角动量 (OAM) 复杂化存在衍射. 一种新的辐射相控制方法抑制了分歧,提高了OAM光束的接收功率和传输距离.
科学领域:
- 光学通信是指光学通信.
- 自由空间光学 (FSO) 是什么?
- 梁传播 梁传播
背景情况:
- 轨道角动量 (OAM) 复杂化是扩大自由空间光学 (FSO) 通信能力的关键技术.
- 为了增加容量所必需的更高阶OAM模式,由于衍射而表现出显著的光束分歧,降低了接收功率.
- 这种分歧限制了FSO系统中的传输距离和多重 OAM 模式的数量.
研究的目的:
- 建议并实验验证多重OAM光束的新型差异抑制方法.
- 为了实现更长的传输距离,并在FSO通信中容纳更多的多重 OAM 模式.
- 为了减轻光束分歧对基于OAM的FSO系统中接收光学功率的有害影响.
主要方法:
- 开发一个辐射相控制技术来操纵多重OAM光束的传播轨迹.
- 辐射相控制多重 (RPCM) OAM光束的实验实施.
- 在不同流条件下对RPCM OAM光束与常规多重 (CM) OAM光束进行比较分析.
主要成果:
- 拟议的RPCM方法有效地抑制了光束分歧,无论OAM模式如何,都保持了接收的光束大小.
- 实验验证证明了RPCM OAM光束用于增强FSO通信的可行性.
- RPCM OAM 束在平均接收功率方面取得了显著的改进,大约比 CM OAM 束在流强度 D/r0=1 和 D/r0=4 时分别高出 25 dB 和 30 dB.
结论:
- 辐射相控制是一种非常有效的策略,用于减轻多重OAM光束的分歧.
- RPCM技术为扩大基于OAM的FSO通信系统的覆盖范围和能力提供了一个有前途的解决方案.
- 这种方法克服了传统OAM复杂化的关键局限性,为更强大,更有效的光学无线通信铺平了道路.
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