Ka频段卫星通信系统雨衰的计算与测量研究

发布时间：2018-04-18 01:12

本文选题：Ka频段卫星通信 + 雨衰　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：随着毫米波技术的发展,卫星通信应用频段已向着大容量、高频段扩展。采用Ka频段大容量卫星通信不仅是我国军事通信应用的必然发展,同时也能为民用领域高速卫星通信多媒体业务提供一种崭新的手段。对于Ka频段卫星通信系统,由于其工作频率高,降雨所引起的信号衰减较为严重。本文首先分析降雨的物理特征,其中包括雨滴形状、收尾速度、降雨强度、尺寸分布等,重点阐述了降雨引起信号功率衰减的机理；其次,运用ITU-R推荐的雨衰计算模型,根据我国气候分布情况,选择了典型观测站的相关参数作为计算依据,计算当地年平均超过P%降雨率的雨衰值,分析了雨衰的分布特点；再次,以小型卫星移动通信地球站为平台,建立雨衰测试系统,详细介绍了测试系统的组成和原理,并对测试系统的测量误差进行了分析,通过在我国部分地区对Ka频段地一空链路上、下行信号降雨衰减的测试,得出了不同降雨率情况下的信号衰减；最后,将测试结果和计算结果进行分析比较,得出计算结果和测试结果在工程化应用中的实际意义,为Ka频段卫星通信系统,尤其是小型卫星通信地球站的系统设计提供较为准确的取值依据。本文采用的研究方法有一定的局限性,本次试验以小型卫星移动通信地球站为基础,接收到的卫星信号信噪比不高,动态范围有限,同时,受时间、试验经费制约,测试的地区、时间有限,所测数值并不能完全反映该地区长期降雨衰减统计特性,在后期的工作中,将选择更多地区进行相关试验,以期获得更多试验数据,对雨衰数据进行补充。
[Abstract]:With the development of millimeter wave technology, the application frequency band of satellite communication has been expanded to large capacity and high frequency band.Ka-band large capacity satellite communication is not only the inevitable development of military communication applications in China, but also provides a new means for high-speed satellite communication multimedia service in civil field.For Ka band satellite communication system, the signal attenuation caused by rainfall is serious because of its high operating frequency.This paper first analyzes the physical characteristics of rainfall, including the shape of raindrops, finishing speed, rainfall intensity, size distribution, etc. The mechanism of signal power attenuation caused by rainfall is described in detail. Secondly, the rain decay calculation model recommended by ITU-R is used.According to the climate distribution in China, the relevant parameters of typical observation stations are selected as the basis of calculation, and the local average annual rainfall rate exceeding P% rainfall rate is calculated, and the distribution characteristics of rain decline are analyzed.Taking the small satellite mobile communication earth station as the platform, the rain decline test system is established. The composition and principle of the test system are introduced in detail, and the measurement error of the test system is analyzed.By testing downlink rainfall attenuation in some areas of China, the attenuation of downlink signal under different rainfall rates is obtained. Finally, the results of test and calculation are analyzed and compared.The practical significance of the calculation results and the test results in the engineering application is obtained, which provides a more accurate basis for the design of the Ka-band satellite communication system, especially the small satellite communication earth station.The research method adopted in this paper has some limitations. This experiment is based on the small satellite mobile communication earth station. The signal to noise ratio (SNR) of the received satellite signal is not high, the dynamic range is limited, at the same time, it is restricted by the time and the test funds.The measured values do not fully reflect the statistical characteristics of long-term rainfall attenuation in the region, and more areas will be selected to carry out the relevant tests in a later period of work, with a view to obtaining more experimental data.Supplement the rain decline data.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN927.2

【参考文献】