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摘要60GHz和118GHz波段处于毫米波非大气窗口频段，在大气中传播时受不同大气条件的影响，电波传输由于吸收和散射产生衰减。本文研究了60GHz和118GHz波段受大气中氧气分子和水蒸气分子的吸收效应以及云雾、降雨、降雪的吸收和散射对毫米波传播产生的衰减。根据适当的模型对各种条件下的60GHz和118GHz波段衰减进行讨论，与相关文献实测数据对比，本论文仿真获得结果接近实测值。首先，根据MPM模型仿真了晴空条件下毫米波的传播特性，明确了氧气吸收带；其次，以云雾、降雨、降雪产生的衰减为主要因素，分析其对毫米波的吸收和散射作用。得出结论：云雾、降雪条件下，含水量越大，对毫米波产生的衰减率值也越大；降雨条件下，降雨率越大毫米波传输的衰减率越大。降雪除了水分吸收作用，还会由于散射产生衰减，但是散射衰减率不会很大。当多种气象条件同时存在时，我们也必须同时考虑多种衰减同时存在。最后对云、雾、雨、雪等大气复合条件下的衰减进行讨论，并讨论了其在雷达方面的实际应用。本文的研究对民用和军用通信、遥感等系统的开发和应用均具有重要的实际意义。21782
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关键词 60GHz、118GHz 毫米波 衰减 MPM模型 云、雨、雾、雪
毕业论文设计说明书（论文）外文摘要
Title Characteristics of non-atmospheric window band millimeter wave propagation in the hydrogel
Abstract
60GHz and 118GHz waveband is the non-atmospheric window waveband, when propagating in atmosphere, it is attenuated for absorption and scattering of different atmospheric condition. In this paper, the attenuation of 60GHz and 118GHz waveband caused by the absorption of oxygen and water, cloud, rain, snow , is researched. According to appropriate model , the attenuated of 60GHz and 118GHz waveband are researched under a variety of conditions. And comparing to the measured data from the related literature, the simulation result in this paper is closed to the measured data. First, based on the MPM model, the propagation characteristics of millimeter-wave is researched and simulate in the condition of clear sky, and then oxygen absorption is verified. Second, considering clouds, rain, snow as the main factors which cause the attenuation,the absorption and scattering effect of millimeter-wave caused by them are researched. In the end it comes to the conclusion that in the condition of clouds, snow, the rate of attenuation is proportional to the water content; And in the condition of rain, the more the water content is , the greater the attenuation is caused. The condition of snow not only has the effect of the absorption of water, but also generate attenuation for the reason of scattering. But the attenuation which is generated by scattering is not greatly. A variety of attenuation must be considered when a variety of weather conditions exist at the same time. Finally, the complex attenuation of the cloud, fog, rain, snow and other atmospheric conditions are discussed, and discuss its practical application in terms of radar.This research is important for developing the millimeter communication，remote-sensing and so on system in civil and military applied to desert region.
Keywords 60GHzand118GHz Millimeter wave attenuation
MPM cloud、rain、fog、snow
目次
1 绪论 3
1.1 研究背景和意义 3
1.2 毫米波传播特性研究概况 3
1.3 论文章节安排 4
2 晴空大气下的衰减特性 5