The latest trends in mobile technology have increased the need for higher spectrum bands from every sector of using wireless applications. As the internet is growing rapidly it has increased the need for wireless services, which require radio spectrum and thus becoming more congested. Engineers show that due to high demand for spectrum, government authorities are regularly introducing schemes to regulate the use of spectrum. New researches are enhancing to resolve the crisis. In order to fix the spectrum for future technologies, propagation studies are required. In this paper an empirical model is proposed for prediction of attenuation due to clouds and fog based on the Rayleigh approximation model. In this model a new concept of calculating dielectric constants of water are also introduced. The implementation results of the proposed model are compared with the other cloud attenuation models. The proposed model proved to be better than the ITU-R model.

移动技术的最新趋势增加了使用无线应用程序的各个领域对更高频段的需求。随着互联网的快速发展，对无线服务的需求增加了，无线服务需要无线电频谱，因此变得更加拥挤。工程师表明，由于对频谱的大量需求，政府当局定期引入计划来规范频谱的使用。解决危机的新研究正在加强。为了确定未来技术的频谱，需要进行传播研究。本文提出了一种基于瑞利近似模型的云和雾衰减预测的经验模型。在该模型中，还引入了计算水的介电常数的新概念。将该模型的实现结果与其他云衰减模型进行了比较。事实证明，所提出的模型优于ITU-R模型。