Rich scattering of the signals in the ultraviolet (UV) band of electromagnetic spectrum enables non-line-of-sight (NLOS) outdoor wireless connectivity. It eliminates the line-of-sight requirement of the links which are using the signals in the infra-red band. Besides scattering losses, UV signals also suffer from atmospheric turbulence-induced fading. The turbulent atmospheric channel causes fluctuations in the received signal intensity of a NLOS ultraviolet (NLOS-UV) link, resulting in power loss and the performance degradation at the receiver. In this study, spatial diversity techniques are investigated as an appealing fading mitigation technique for NLOS-UV systems over atmospheric turbulence channels. In particular, the outage probabilities of multiple-input-single-output (MISO), single-input-multiple-output (SIMO), and multiple-input-multiple-output (MIMO) links are studied, and the outage performances are investigated for different system configurations. Closed-form expressions are derived for the outage probability of MISO, SIMO, and MIMO systems, and the accuracy of the derivations is confirmed through Monte Carlo simulations. The outage probability of single-input-single-output link is also derived as a benchmark. The results demonstrate significant performance improvements through deployment and proper configuration of MIMO systems in NLOS-UV communication links.

中文翻译：

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大气湍流信道下MIMO NLOS-UV通信系统的中断分析

电磁频谱的紫外线（UV）波段中信号的丰富散射实现了非视距（NLOS）室外无线连接。它消除了使用红外波段信号的链路的视线要求。除散射损耗外，紫外线信号还会遭受大气湍流引起的衰落。湍流的大气通道会导致NLOS紫外线（NLOS-UV）链路的接收信号强度发生波动，从而导致功率损耗和接收机性能下降。在这项研究中，研究了空间分集技术作为大气湍流通道上NLOS-UV系统的一种有吸引力的衰落缓解技术。特别是多输入单输出（MISO），单输入多输出（SIMO），研究了多输入多输出（MIMO）链路，并研究了不同系统配置的中断性能。对于MISO，SIMO和MIMO系统的中断概率，可以得出闭合形式的表达式，并且可以通过蒙特卡洛模拟来确定推导的准确性。单输入单输出链路的中断概率也作为基准。结果表明，通过在NLOS-UV通信链路中部署和正确配置MIMO系统，可以显着提高性能。单输入单输出链路的中断概率也作为基准。结果表明，通过在NLOS-UV通信链路中部署和正确配置MIMO系统，可以显着提高性能。单输入单输出链路的中断概率也作为基准。结果表明，通过在NLOS-UV通信链路中部署和正确配置MIMO系统，可以显着提高性能。