搜索结果: 1-7 共查到“知识库 超高频无线电物理”相关记录7条 . 查询时间(0.978 秒)
Variation of the feedback coefficient with R12 and the geographic latitude in 1-h ahead forecast of f0 F2
forecast feedback critical frequency
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2015/9/25
The «prediction» and «forecast» of the critical frequency of the F 2 layer (f0 F2 ) is an important issue for frequency planning in short wave radio communications. In this context...
基于双曲线性修正斜距模型的弹载SAR成像方法
弹载合成孔径雷达 双曲斜距 线性修正因子 驻相点原理
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2013/11/19
在弹载合成孔径雷达(synthetic aperture radar, SAR)下降段成像中,由于弹体存在较大的俯冲下降速度和加速度,回波信号的二维频谱表示式难以有效获得,给后续成像处理带来困难。针对该问题,提出了一种基于双曲线性修正斜距模型的弹载SAR成像方法,通过构造双曲函数形式的斜距表示式并引入线性修正因子,对弹载SAR斜距历程进行合理近似|并以修正后的斜距式为基础,利用驻相点原理(prin...
频谱感知是认知无线电中的关键技术,认知用户(非授权用户)只有在频段空闲时才能接入,然而认知用户检测概率与它所处位置的信噪比是密切相关的,针对认知用户所处位置的不确定,通过对认知用户到授权用户距离的统计平均,来获取认知用户对授权用户检测概率的统计平均量。结果分析表明,在不知道认知用户位置及信噪比这些先验条件情况下,对不同频段和不同发射信噪比的授权用户进行检测,可有效地获知该频段是否被授权用户占用。
Searches for Physics Beyond the Standard Model at CMS
Physics Standard Model CMS
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2011/1/4
Recent results on searches for physics beyond the Standard Model at Large Hadron Collider are presented, based on early LHC data in proton-proton collisions at p s = 7 TeV collected by the CMS experim...
Ross Ice Shelf in situ radio-frequency ice attenuation
Ross Ice Shelf situ radio-frequency ice attenuation
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2011/1/5
We have measured the in situ average electric field attenuation length hLi for
radio-frequency signals broadcast vertically through the Ross Ice Shelf. We chose a location,
Moore Embayment, south o...
Quantum singular operator limits of thin Dirichlet tubes via $\Gamma$-convergence
Quantum singular operator limits thin Dirichlet tubes $\Gamma$-convergence
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2010/11/11
The $\Gamma$-convergence of lower bounded quadratic forms is used to study the singular operator limit of thin tubes (i.e., the vanishing of the cross section diameter) of the Laplace operator with Di...