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Integrated of Proximity-Coupling High-Order Modes Patch Antenna with Solar Cells for Sustainable Communication
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作者 Jingyu Lai Yu Luo +2 位作者 Ningning Yan Wenxing An Kaixue Ma 《China Communications》 SCIE CSCD 2023年第6期72-81,共10页
An integration of single-layer proximitycoupling patch antenna and solar cells with bandwidth enhancement and optical energy harvesting is proposed for sustainable communication.For this purpose,many dual-function com... An integration of single-layer proximitycoupling patch antenna and solar cells with bandwidth enhancement and optical energy harvesting is proposed for sustainable communication.For this purpose,many dual-function components are selected for designing the miniaturized solar cell antenna.On the one hand,by greatly affecting the current flow of the rectangular patch,vias and proximity-coupling are introduced to control the resonance modes frequency and matching,respectively,for wideband application,and the radiation performance property can be achieved by high-order mode.On the other hand,vias and proximity-coupling are beneficial to complete direct-current(DC)loop of solar cell and improve compatibility of DC-RF(radio frequency),whereas a high-order mode is beneficial to increase the area of collected light energy.To prove the working principle,fabricated and manufactured solar cell antenna.The measured and simulated results illustrate that the solar cell antenna gain is raised to as high as 9.27 d Bi in4.37 to 5.06 GHz applied to fifth generation communication(5G). 展开更多
关键词 solar cell PATCH integration compressed high-order mode high gain proximity-coupling
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特软地层井孔中各模式波的传播特征 被引量:3
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作者 陈雪莲 范宜仁 许孝凯 《物探化探计算技术》 CAS CSCD 2009年第5期460-465,共6页
针对浅层及海底沉积软地层声学参数准确提取的迫切需求,采用实轴积分法数值计算了单极和偶极声源,在特软地层井孔中激发的全波波形,并考察了井径和地层纵横波速度变化,对全波波形中各个模式波的影响。数值计算结果表明,漏能纵波的幅度... 针对浅层及海底沉积软地层声学参数准确提取的迫切需求,采用实轴积分法数值计算了单极和偶极声源,在特软地层井孔中激发的全波波形,并考察了井径和地层纵横波速度变化,对全波波形中各个模式波的影响。数值计算结果表明,漏能纵波的幅度随着地层纵横波速度比的增大而增强,这也是利用漏能纵波衰减提取地层横波速度的基础。通过对比漏能纵波的频散曲线,验证了从偶极子声源在特软地层井孔激发的漏能纵波中,提取地层的纵波慢度比单极子声源更有效。随着仪器和井壁间流体层厚度的增加,斯通利波和弯曲波的幅度逐渐减弱,且主频向低频方向偏移。 展开更多
关键词 特软地层 漏能纵波 弯曲波 斯通利波 井径
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声波测井中首波与次首波的理论研究 被引量:4
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作者 王秀明 韩德旺 王冠贵 《地球物理学报》 SCIE EI CAS CSCD 北大核心 1990年第6期733-739,共7页
本文讨论了裸眼井中由点状声源激发的首波与次首波问题,认为:首波与次首波分别是以地层纵波速度V_c和地层横波速度V_s传播的几何衰减波。同时给出了泄漏波的解析式,而泄漏纵波和泄漏横波的截止频率分别为远场处的首波与次首波的传播特... 本文讨论了裸眼井中由点状声源激发的首波与次首波问题,认为:首波与次首波分别是以地层纵波速度V_c和地层横波速度V_s传播的几何衰减波。同时给出了泄漏波的解析式,而泄漏纵波和泄漏横波的截止频率分别为远场处的首波与次首波的传播特征频率。 展开更多
关键词 声波 测井 首波 次首波 频率
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Leaky modes and their contributions to the compressional head wave in a borehole excited by a dipole source 被引量:1
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作者 ZHANG XiuMei ZHANG HaiLan WANG XiuMing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第5期676-684,共9页
A method of studying the contributions of leaky modes to the wave field is presented based on the analysis of the Riemann surface structure of the characteristic function, and the sensitivities of con- tributions to v... A method of studying the contributions of leaky modes to the wave field is presented based on the analysis of the Riemann surface structure of the characteristic function, and the sensitivities of con- tributions to various factors of interest are examimed. Numerical results show that their contributions to the compressional head wave are related to the distributions of complex poles on (-1, -1) and (0, -1) Riemann sheets on the frequency-wavenumber (ω - k) plane. For fast formations, their contributions are small, while for slow formations with large Poisson’s ratio, their contributions are large because of those complex poles with small imaginary parts near the compressional vertical branch cut. The decaying factor of the contributions of leaky modes is approximately proportional to 1/distance2. 展开更多
关键词 DIPOLE SOURCE RIEMANN surface leaky modes compressional head wave
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A Ka-band Solid-state Transmitter Cloud Radar and Data Merging Algorithm for Its Measurements 被引量:8
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作者 Liping LIU Jiafeng ZHENG Jingya WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第4期545-558,共14页
This study concerns a Ka-band solid-state transmitter cloud radar, made in China, which can operate in three different work modes, with different pulse widths, and coherent and incoherent integration numbers, to meet ... This study concerns a Ka-band solid-state transmitter cloud radar, made in China, which can operate in three different work modes, with different pulse widths, and coherent and incoherent integration numbers, to meet the requirements for cloud remote sensing over the Tibetan Plateau. Specifically, the design of the three operational modes of the radar(i.e., boundary mode M1, cirrus mode M2, and precipitation mode M3) is introduced. Also, a cloud radar data merging algorithm for the three modes is proposed. Using one month's continuous measurements during summertime at Naqu on the Tibetan Plateau,we analyzed the consistency between the cloud radar measurements of the three modes. The number of occurrences of radar detections of hydrometeors and the percentage contributions of the different modes' data to the merged data were estimated.The performance of the merging algorithm was evaluated. The results indicated that the minimum detectable reflectivity for each mode was consistent with theoretical results. Merged data provided measurements with a minimum reflectivity of -35 dBZ at the height of 5 km, and obtained information above the height of 0.2 km. Measurements of radial velocity by the three operational modes agreed very well, and systematic errors in measurements of reflectivity were less than 2 dB. However,large discrepancies existed in the measurements of the linear depolarization ratio taken from the different operational modes.The percentage of radar detections of hydrometeors in mid- and high-level clouds increased by 60% through application of pulse compression techniques. In conclusion, the merged data are appropriate for cloud and precipitation studies over the Tibetan Plateau. 展开更多
关键词 data merging algorithm operational mode Ka-band radar cloud Tibetan Plateau pulse compression technique
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变质砂板岩Ⅰ型断裂韧度各向异性初探 被引量:2
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作者 李忠洪 刘建锋 郑小芳 《力学与实践》 北大核心 2018年第5期520-525,共6页
Ⅰ型断裂韧度是岩石的主要特征力学参数,且影响因素很多。目前,国内可查的细观层理对岩石Ⅰ型断裂韧度影响的相关研究较少。试验利用隧道开挖中的变质砂板岩,测试了横向、纵向和无细观层理砂板岩纵波波速,并采用三点弯曲圆梁方法研究了... Ⅰ型断裂韧度是岩石的主要特征力学参数,且影响因素很多。目前,国内可查的细观层理对岩石Ⅰ型断裂韧度影响的相关研究较少。试验利用隧道开挖中的变质砂板岩,测试了横向、纵向和无细观层理砂板岩纵波波速,并采用三点弯曲圆梁方法研究了相应砂板岩试件的Ⅰ型断裂力学性质。试验表明KIC、断裂破坏挠度、细观层理和纵波波速间存在相关关系,根据试验成果提出各向异性系数Y的概念,利用各向异性系数Y计算的K IC值与实测的相应试件KIC符合较好。 展开更多
关键词 变质砂板岩 细观层理 Ⅰ型断裂韧度 纵波波速 各向异性
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Gyrokinetic Simulation of Magnetic Compressional Modes in General Geometry
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作者 Peter Porazik Zhihong Lin 《Communications in Computational Physics》 SCIE 2011年第9期899-911,共13页
A method for gyrokinetic simulation of low frequency(lower than the cyclotron frequency)magnetic compressional modes in general geometry is presented.The gyrokinetic-Maxwell system of equations is expressed fully in t... A method for gyrokinetic simulation of low frequency(lower than the cyclotron frequency)magnetic compressional modes in general geometry is presented.The gyrokinetic-Maxwell system of equations is expressed fully in terms of the compressional component of the magnetic perturbation,δBk,with finite Larmor radius effects.This introduces a"gyro-surface"averaging ofδBk in the gyrocenter equations of motion,and similarly in the perpendicular Ampere’s law,which takes the form of the perpendicular force balance equation.The resulting system can be numerically implemented by representing the gyro-surface averaging by a discrete sum in the configuration space.For the typical wavelength of interest(on the order of the gyroradius),the gyro-surface averaging can be reduced to averaging along an effective gyro-orbit.The phase space integration in the force balance equation can be approximated by summing over carefully chosen samples in the magnetic moment coordinate,allowing for an efficient numerical implementation. 展开更多
关键词 Finite Larmor radius effects gyrokinetic simulation compressional modes gyrosurface average
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Multi-spacecraft observations of ULF waves during the recovery phase of magnetic storm on October 30, 2003 被引量:11
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作者 YongFu Wang SuiYan Fu +4 位作者 QiuGang Zong Biao Yang ZuYin Pu Lun Xie XuZhi Zhou 《Science China(Technological Sciences)》 SCIE EI CAS 2008年第10期1772-1785,共14页
Based on observations obtained by Cluster C1, GOES 10, 12, and Polar, the global ULF wave properties are studied during the recovery phase of a very intense magnetic storm-Halloween storm (October 31, 2003, 21:00-23:0... Based on observations obtained by Cluster C1, GOES 10, 12, and Polar, the global ULF wave properties are studied during the recovery phase of a very intense magnetic storm-Halloween storm (October 31, 2003, 21:00-23:00 UT). The results indicate that the ULF waves’ properties observed by different satellites, such as amplitude, period, etc. show large variations. This can be interpreted as that Field Line Resonance (FLR) might take place in the region where Cluster C1 passed. The compressional wave of the cavity mode coupled with FLR’s shear Alfven wave and fed energy to the latter, forming a large-amplitude toroidal mode. From the point of period, Cluster C1 observed the shortest period, GOES 10, 12 observed the middle, while Polar observed the longest. The wave period of toroidal mode observed by Cluster C1 kept almost unchanging when Cluster C1 passed L range from 11.7 to 5.3. Using the Squared Wavelet Coherence analysis method, we estimated that the FLR region in the dayside magnetosphere could expand to at least 4 local time widths. The toroidal mode observed by Polar was a standing wave, while the pol-oidal mode was a propagating wave, the observation results could be well ex-plained by the waveguide mode theory. Since the solarwind speed Vx was -800 km/s and the dynamic pressure varied little, we speculated that the source of the ULF wave was the Kelvin-Helmholtz instability at the magnetopause triggered by high speed solarwind. 展开更多
关键词 magnetic STORM ULF wave poloidal mode TOROIDAL mode compressional mode cavity mode Field Line Resonance (FLR)
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Recent progress on ULF wave and its interactions with energetic particles in the inner magnetosphere 被引量:16
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作者 Theodore A. FRITZ 《Science China(Technological Sciences)》 SCIE EI CAS 2008年第10期1620-1625,共6页
The global distribution properties of Ultra Low Frequency wave (ULF) in the inner magnetospgere and its interactions with energetic particles, such as the wave-particle resonance, modulation, and particle acceleration... The global distribution properties of Ultra Low Frequency wave (ULF) in the inner magnetospgere and its interactions with energetic particles, such as the wave-particle resonance, modulation, and particle acceleration, are active topics in space physics research. These problems are fundamentally important issues to understand the energy transport from the solar wind into the magnetosphere. In this paper we briefly reviewed the recent research progress on ULF wave and its interactions with energetic particles in the inner magnetosphere; furthermore, we suggested some open questions for future study. 展开更多
关键词 radiation BELT PARTICLE PARTICLE acceleration ULF wave compressional mode cavity mode poloidal mode TOROIDAL mode Field Line Resonance (FLR) ENERGETIC particles modulation
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