Abstract Radio-over-Free-Space Optics (RoFSO) is a key technology for providing high-speed communication links in rural areas. In this work, an orthogonal frequency division multiplexing based RoFSO transmission link has been designed by adopting hybrid wavelength division multiplexing (WDM), mode division multiplexing (MDM) and multibeam technique. The proposed link is investigated under heavy fog weather conditions and its performance is compared for 1-beam and 4-beams transmission using numerical simulations. The numerical results show faithful transportation of high-speed data at 2000 m with acceptable performance of the link. Furthermore, the link performance is compared with previously reported works and the proposed RoFSO link with hybrid WDM-MDM-multibeam technique demonstrates an enhanced link range and transmission capacity performance.

中文翻译：

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使用波分复用-模分复用-多波束技术的高速自由空间无线电光链路

摘要 自由空间无线电（RoFSO）是为农村地区提供高速通信链路的关键技术。在这项工作中，采用混合波分复用（WDM）、模分复用（MDM）和多波束技术设计了基于正交频分复用的 RoFSO 传输链路。在大雾天气条件下研究了建议的链路，并使用数值模拟比较了 1 光束和 4 光束传输的性能。数值结果表明，高速数据在 2000 米处的可靠传输以及可接受的链路性能。此外，将链路性能与先前报告的工作进行比较，并且提议的 RoFSO 链路采用混合 WDM-MDM-多波束技术，展示了增强的链路范围和传输容量性能。