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穿透地层的矿井地下无线通信系统设计方案探析 被引量:14
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作者 陶晋宜 《太原理工大学学报》 CAS 2000年第1期39-42,52,共5页
针对穿透地层无线通信的特点,采用终端短路单级天线及单边带调制和弱信号接收技术。
关键词 单边带调制 矿井 地下无线通信 穿透地层 设计
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甚低频电磁波穿透地层无线通信系统的问题分析
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作者 林亮 《电子技术与软件工程》 2015年第2期45-45,共1页
本文依循经典特性的理论,明辨了甚低频范畴内的电磁波,在地层架构之中的传播状态。甚低频特性的电磁波,密切关联着无线架构以内的通信路径。无线通信关涉的系统,可以经由地层,去运送明晰的信号。这样安设的系统,为各时段的通信顺畅,供... 本文依循经典特性的理论,明辨了甚低频范畴内的电磁波,在地层架构之中的传播状态。甚低频特性的电磁波,密切关联着无线架构以内的通信路径。无线通信关涉的系统,可以经由地层,去运送明晰的信号。这样安设的系统,为各时段的通信顺畅,供应了保障。 展开更多
关键词 甚低频电磁波 穿透地层 无线通信系统
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关于频率电磁测深几个问题的探讨(五)——频率电磁测深中电磁场波型及意义 被引量:2
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作者 陈明生 《煤田地质与勘探》 CAS CSCD 北大核心 2014年第1期64-67,共4页
引出水平分层大地面上水平电偶极源及垂直磁偶极源的电磁场分量表达式,对式中核函数进行了变换,分析所含的波型及其与场区的关系,指出了TE型场、TM型场和TEM型场穿透地层的能力。根据波型与地层作用特点,优化电磁场分量,以提高频率电磁... 引出水平分层大地面上水平电偶极源及垂直磁偶极源的电磁场分量表达式,对式中核函数进行了变换,分析所含的波型及其与场区的关系,指出了TE型场、TM型场和TEM型场穿透地层的能力。根据波型与地层作用特点,优化电磁场分量,以提高频率电磁测深的探测效果。 展开更多
关键词 水平电偶极 垂直磁偶极 电磁场分量 波型 穿透地层 频率电磁测深 探测效果
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A numerical investigation of the acoustic mode waves in a deviated borehole penetrating a transversely isotropic formation 被引量:2
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作者 LIU Le LIN WeiJun +1 位作者 ZHANG HaiLan WANG XiuMing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第8期49-57,共9页
A 2.5-dimensional method in frequency wave-number domain is developed to investigate the mode waves in a deviated borehole penetrating a transversely isotropic formation. The phase velocity dispersion characteristics ... A 2.5-dimensional method in frequency wave-number domain is developed to investigate the mode waves in a deviated borehole penetrating a transversely isotropic formation. The phase velocity dispersion characteristics of the fast and slow flexural mode waves excited by a dipole source are computed accurately at various deviation angles for both hard and soft formations. The sensitivities of the flexural mode waves to all elastic constants in a transversely isotropic formation are calculated. Numerical results show that, for a soft formation, the fast flexural mode wave is dominated by c66 at high deviation angles and low frequencies, while the slow flexural mode wave is dominated by c44 at the same conditions. Waveforms in time domain are also presented to support the conclusions. 展开更多
关键词 deviated borehole transverse isotropy acoustic mode waves dispersion curve sensitivity analysis
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Electric field penetration into Earth's ionosphere:a brief review for 2000–2013 被引量:1
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作者 魏勇 赵必强 +1 位作者 李国主 万卫星 《Science Bulletin》 SCIE EI CAS CSCD 2015年第8期748-761,M0003,共15页
Electric field penetration is a consequence of solar wind interaction with planetary magnetosphere and/or ionosphere. For both Earth with intrinsic magnetosphere and Mars/Venus without intrinsic magnetosphere, the pen... Electric field penetration is a consequence of solar wind interaction with planetary magnetosphere and/or ionosphere. For both Earth with intrinsic magnetosphere and Mars/Venus without intrinsic magnetosphere, the penetration electric field causes various kinds of global and local electrodynamic response of the ionosphere to the solar wind electric field, especially the plasma motion in the ionosphere. Within the first 14 years of the twenty-first century, the cause and effect of the electric field penetra- tion on Earth has been investigated extensively and understood more deeply. Here we review the progress acquired on the patterns and drivers of the penetration electric field, and its influences on the plasma distribution and the equatorial spread F in the mid- and low-latitude ionosphere. From the perspective of comparative study, we also shortly introduce the new results for Mars. What has become clear is that our understanding of electric field penetration has been significantly improved, but ultimately the crucial details of the global picture still remain un- known. Looking forward to the future research of the electric field penetration in Earth's ionosphere, the break- through relies on new instruments built up at different longitudes to improve the global coverage of the observa- tion. An integrated network of instrument is necessary to reveal the longitude and local-time dependence of the electric field penetration and shed new light on the physical details of the global ionospheric processes driven by the electric field penetration. 展开更多
关键词 Electric field penetration IONOSPHERE MAGNETOSPHERE
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