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Wideband Reconfigurable Millimeter-Wave Linear Array Antenna Using Liquid Crystal for 5G Networks 认领
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作者 Ali El Hajj Hassan Najib Fadlallah +2 位作者 Mohammad Rammal Georges Zakka El Nashef Elias Rachid 《无线工程与技术(英文)》 2021年第1期1-14,共14页
The advanced design of a 10 × 1 linear antenna array system with the capa-bility of frequency tunability using GT3-23001 liquid crystal (LC) is pro-posed. The design for this reconfigurable wideband antenna array... The advanced design of a 10 × 1 linear antenna array system with the capa-bility of frequency tunability using GT3-23001 liquid crystal (LC) is pro-posed. The design for this reconfigurable wideband antenna array for 5G ap-plications at Ka-band millimeter-wave (mmw) consists of a double layer of stacked patch antenna with aperture coupled feeding. The bias voltage over LC varies from 0 V to 10.6 V to achieve a frequency tunability of 1.18 GHz. The array operates from 25.3 GHz to 33.8 GHz with a peak gain of 19.2 dB and a beamwidth of 5.2<span style="white-space:nowrap;">&#176</span> at 30 GHz. The proposed reconfigurable antenna ar-ray represents a real and efficient solution for the recent and future mmw 5G networks. The proposed antenna is suitable for 5G base stations in stadiums, malls and convention centers. It is proper for satellite communications and radars at mmw. 展开更多
关键词 5G Networks Liquid Antenna Liquid Crystal Frequency Reconfigurability Antenna Array MILLIMETER-WAVE
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文章速递某型教练机口盖裂纹分析与研究 认领
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作者 左晓娟 吴根林 +1 位作者 张伟 李灿山 《教练机》 2021年第1期49-52,共4页
某型教练机在机身中后段机腹左侧部位的一处口盖,其上安装通讯天线的位置出现裂纹。为解决口盖裂纹问题,从设计、工艺、制造、使用环境等方面对故障原因进行分析,结合口盖裂纹部位的理化分析结果,得到裂纹的产生原因,并提出了改进措施。
关键词 口盖 天线 裂纹 振动
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天线振动对数字无线通信系统影响机制研究 认领
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作者 韩明超 李皓琰 +1 位作者 孙国良 汲书强 《电波科学学报》 北大核心 2021年第1期136-141,共6页
振动会造成天线相对位置变化,产生干扰信号,导致通信质量下降.基于振动天线辐射理论模型,定量分析了四进制相移键控(quadrature phase shift keying,QPSK)系统天线振动对通信性能的影响,推导了QPSK系统天线在振动条件下系统误符率(symbo... 振动会造成天线相对位置变化,产生干扰信号,导致通信质量下降.基于振动天线辐射理论模型,定量分析了四进制相移键控(quadrature phase shift keying,QPSK)系统天线振动对通信性能的影响,推导了QPSK系统天线在振动条件下系统误符率(symbol error rate,SER)公式,并通过计算机仿真验证了理论推导的正确性.理论分析和仿真结果表明,通信系统工作载波频率越高、天线振动加速度越大、振动频率越小,数字通信系统性能恶化越严重,该结果对天线结构设计、安装和无线通信网络分析规划提供了理论基础. 展开更多
关键词 天线 振动 数字通信 系统误符率(SER) 四进制相移键控(QPSK)
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广播电视卫星地球站专业技术设备系统配置中值得探讨的几个问题 认领
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作者 韦漫涛 《中国有线电视》 2021年第1期30-34,共5页
通过对广播电视卫星地球站专业技术设备系统配置中信号源引接系统的选择方式问题、调制器输入端口的使用和中频切换开关的使用问题、上变频器的连接方式及射频切换开关的使用问题、主备两套系统与主备两面上行天线的连接使用问题、接收... 通过对广播电视卫星地球站专业技术设备系统配置中信号源引接系统的选择方式问题、调制器输入端口的使用和中频切换开关的使用问题、上变频器的连接方式及射频切换开关的使用问题、主备两套系统与主备两面上行天线的连接使用问题、接收系统低噪声放大器(LNA)和低噪声变频器(LNB)的连接使用问题进行讨论,制定了一套功能完善、稳定可靠、有冗余性的高清晰度卫星电视上行传输系统。 展开更多
关键词 卫星地球站 信号源 调制器 上变频 天线 低噪放 系统
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通过复数几何光学对一种天线面型诊断方法的改进 认领
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作者 姚强 金惠良 叶骞 《高技术通讯》 CAS 北大核心 2021年第2期180-187,共8页
通过天线所辐射的电场幅值来求解天线面形变是一种新的天线面型诊断方法,但是由于该方法基于实数几何光学(RGO),忽略了高斯馈源的影响,从而导致了一定的误差。本文通过复数几何光学(CGO)对高斯馈源所发射的电磁波的复数相位进行了研究,... 通过天线所辐射的电场幅值来求解天线面形变是一种新的天线面型诊断方法,但是由于该方法基于实数几何光学(RGO),忽略了高斯馈源的影响,从而导致了一定的误差。本文通过复数几何光学(CGO)对高斯馈源所发射的电磁波的复数相位进行了研究,推导得出了较准确的天线面形变和天线辐射场幅值之间的关系表达式。在此基础上,提出了一种迭代算法来求解天线面形变,仿真结果表明该方法可以有效提高天线面形变的求解精度。 展开更多
关键词 实数几何光学(RGO) 复数几何光学(CGO) 反射天线 高斯馈源 表面形变
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卫星固定站天线控制系统改造的探讨 认领
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作者 陈涛 徐平 《数字通信世界》 2021年第2期29-30,36,共3页
卫星固定站是指在特定站点的卫星通信地球站,通常是通过同步轨道通信卫星进行卫星业务的通信。卫星固定站大多使用的是2.4 m-7.3 m静中通天线,早期的工程施工中大部分天线未安装自动控制系统,靠手动控制驱动电机进行对星。文章对Ku频段... 卫星固定站是指在特定站点的卫星通信地球站,通常是通过同步轨道通信卫星进行卫星业务的通信。卫星固定站大多使用的是2.4 m-7.3 m静中通天线,早期的工程施工中大部分天线未安装自动控制系统,靠手动控制驱动电机进行对星。文章对Ku频段卫星固定站天线控制系统改造进行探讨,提出更好的改造方案。 展开更多
关键词 卫星 固定站 天线
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某车型Glonass紧急呼叫系统的布置及应用 认领
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作者 吴隽 张华春 《汽车电器》 2021年第1期35-36,共2页
根据俄罗斯法规TP TC 2018/2011轮式交通安全规则规定,出口到俄罗斯的车型均需要配备有ERA-Glonass系统。目前,大部分进入俄罗斯市场的新车,采用俄罗斯当地供应商开发的成套Glonass系统,以后装模式安装到整车上。本文阐述的是一种新的... 根据俄罗斯法规TP TC 2018/2011轮式交通安全规则规定,出口到俄罗斯的车型均需要配备有ERA-Glonass系统。目前,大部分进入俄罗斯市场的新车,采用俄罗斯当地供应商开发的成套Glonass系统,以后装模式安装到整车上。本文阐述的是一种新的开发模式以及系统零部件的布置及应用。 展开更多
关键词 ERA模块 SOS按键 扬声器 麦克风 天线
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Confinement and antenna effect for ultrasmall Y_(2)O_(3):Eu_(3+) nanocrystals supported by MOF with enhanced near-UV light absorption thereby enhanced luminescence and excellently multifunctional applications 认领
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作者 Hongyi Xu Wenjing Yu +2 位作者 Kai Pan Guofeng Wang Peifen Zhu 《纳米研究:英文版》 SCIE EI CAS 2021年第3期720-729,共10页
A novel host-guest luminous system with enhanced near-UV light absorption thereby enhanced luminescence are designed based on the synergism of quantum confinement,spatial confinement,and antenna effect,where ultrasmal... A novel host-guest luminous system with enhanced near-UV light absorption thereby enhanced luminescence are designed based on the synergism of quantum confinement,spatial confinement,and antenna effect,where ultrasmall Y_(2)O_(3):Eu_(3+)nanocrystals are fixed inside MOF(Eu/Y-BTC)as supporting structure.The Eu/Y-BTC not only limits the size and leads to lattice distortion of Y_(2)O_(3):Eu_(3+)nanocrystals and controls the distance between nanocrystals,but also promotes the light absorption and emission.The significantly red-shifted and broadened charge transfer band of Y_(2)O_(3):Eu_(3+)/(Eu/Y-BTC)leads to the excellent applications of Y_(2)O_(3):Eu_(3+)in white light-emitting diodes(LEDs).Our results show that white light with superior color quality(CRI>90)and extremely high luminous efficacy(an LER of 335 lm/W)could be achieved using Y_(2)O_(3):Eu_(3+)/(Eu/Y-BTC)as red phosphor.The Y_(2)O_(3):Eu_(3+)/(Eu/Y-BTC)also improves the photoelectric performance of dye-sensitized solar cells(DSSCs),not only because Y_(2)O_(3):Eu_(3+)/(Eu/Y-BTC)has a large specific surface area and the adsorption amount of the dye is increased,but also because the valence band position of Y_(2)O_(3):Eu_(3+)/(Eu/Y-BTC)is 2.41 eV,which can provide an additional energy level between the TiO2 and dye,promoting electron transfer.For these advantageous features,the multifunctional Y_(2)O_(3):Eu_(3+)/(Eu/Y-BTC)composite product will open new avenues in white LEDs and DSSCs. 展开更多
关键词 confinement effect antenna effect enhanced luminescence ultrasmall Y_(2)O_(3):Eu_(3+)nanocrystals MOFs multifunctional applications
一种阵列天线的去耦方法研究 认领
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作者 丁媛媛 王岫鑫 李晓恩 《现代雷达》 北大核心 2021年第2期67-71,共5页
基于小型化超宽带共面波导馈电的Y型单极子天线,构建了一种2×4规模的天线阵列,研究了去耦中和线和去耦隔离臂的工作原理,进行耦合消除分析,比较了两种去耦合方法对天线阵列的影响。仿真表明:该阵列的阻抗带宽为2.4GHz~3.5GHz,隔离... 基于小型化超宽带共面波导馈电的Y型单极子天线,构建了一种2×4规模的天线阵列,研究了去耦中和线和去耦隔离臂的工作原理,进行耦合消除分析,比较了两种去耦合方法对天线阵列的影响。仿真表明:该阵列的阻抗带宽为2.4GHz~3.5GHz,隔离度高于15dB,达到阵列天线的去耦效果,为后续的工程实践提供了技术支撑。 展开更多
关键词 天线 去耦 通信技术 仿真 阵列
机载卫星通信天线跟踪误差分析 认领
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作者 田捷力 李麒 +2 位作者 邓军 顾田航 顾新 《通信技术》 2021年第3期745-749,共5页
随着机载卫星通信的工作频段向着宽频带和多频段拓展,Ku/Ka双频段天线已成为目前发展的主流。双频段天线的指向跟踪方式直接影响卫星通信的性能,而天线系统各项误差可导致天线的指向精度、跟踪精度不能满足动载体快速、可靠与实时捕获... 随着机载卫星通信的工作频段向着宽频带和多频段拓展,Ku/Ka双频段天线已成为目前发展的主流。双频段天线的指向跟踪方式直接影响卫星通信的性能,而天线系统各项误差可导致天线的指向精度、跟踪精度不能满足动载体快速、可靠与实时捕获卫星的需求,导致卫星链路中断,数据丢失,无法正常通信。因此,介绍了机载Ku/Ka双频段天线系统的组成和采用的跟踪方式,分析在不同的跟踪方式下指向误差和跟踪误差的产生因素,并提出改善误差的解决方式,估算跟踪精度。 展开更多
关键词 机载 天线 指向误差 跟踪误差
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关于应答器接收天线的安装位置探讨 认领
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作者 徐效宁 褚伊郎君 +1 位作者 刘磊 朱建设 《铁路通信信号工程技术》 2021年第2期18-21,共4页
研究ETCS的相关规范,结合CTC S应答器的应用原则,探讨应答器接收天线的安装位置,为应答器接收天线在动车组和机车的安装标准提供一定的参考。
关键词 应答器 天线 欧洲列车运行控制系统 中国列车运行控制系统 动车组 机车
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Adaptive Secure Transmission for Wireless Powered Communication Networks 认领
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作者 Yong Wang Weiwei Yang +3 位作者 Tao Zhang Yong Chen Xiaohui Shang Quan Wang 《中国通信:英文版》 SCIE 2021年第3期155-173,共19页
This paper investigates secure transmission in a wireless powered communication network(WPCN)with an energy harvesting(EH)source configured with multiple antennas.In the WPCN,the EH source harvests energy from the rad... This paper investigates secure transmission in a wireless powered communication network(WPCN)with an energy harvesting(EH)source configured with multiple antennas.In the WPCN,the EH source harvests energy from the radio frequency(RF)signals broadcasted by a power beacon(PB),and purely relies on the harvested energy to communicate with the destination in the presence of passive eavesdroppers.It is noteworthy that the RF-EH source is equipped with a finite energy storage to accumulate the harvested energy for the future usage.Moreover,due to energy-constraint and complexitylimitation,the multi-antenna source is only configured with a single RF-chain.To enhance the security for the WPCN,we propose two adaptive transmission schemes,i.e.,energy-aware transmit antenna selection(EATAS)and energy-aware differential spatial modulation(EADSM).According to the energy status and the channel quality,the source adaptively decides whether to transmit confidential information or harvest RF energy.To evaluate the secrecy performance of the proposed schemes,we first study the evolution of the energy storage,and then derive the analytical expressions of connection outage probability(COP),secrecy outage probability(SOP)and efficient secrecy throughput(EST).Numerical results demonstrate that our proposed schemes outperform the existing schemes,i.e.,time-switching based TAS(TS-TAS)Received:May 19,2020 Revised:Sep.13,2020 Editor:Deli Qiao and accumulate-then-transmit(ATT).And,increasing the transmit power of the PB or the capacity of the source’s energy storage is helpful to improve the secrecy performance.Moreover,there exists an optimal transmission rate for each proposed scheme to achieve best secrecy performance. 展开更多
关键词 physical layer security energy harvesting markov chain transmit antenna selection differential spatial modulation
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一种应用于VICTS天线的组合跟踪算法 认领
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作者 刘祥 陆云龙 +2 位作者 黄季甫 鲁严 杨洋 《微波学报》 北大核心 2021年第1期50-54,共5页
可变倾角连续断面节阵列(VICTS)天线在使用单一跟踪算法跟踪卫星时,存在跟踪速度和跟踪精度之间的矛盾,导致天线不能稳定地跟踪卫星。文章在分析VICTS天线的基础上对步进跟踪算法进行改进,提出一种基于程序跟踪、步进跟踪的组合跟踪算... 可变倾角连续断面节阵列(VICTS)天线在使用单一跟踪算法跟踪卫星时,存在跟踪速度和跟踪精度之间的矛盾,导致天线不能稳定地跟踪卫星。文章在分析VICTS天线的基础上对步进跟踪算法进行改进,提出一种基于程序跟踪、步进跟踪的组合跟踪算法。通过设定信标AGC阈值把跟踪状态分为程序跟踪、步进跟踪,并将跟踪态和信标AGC值作为跟踪状态的切换条件,保证了天线工作时的跟踪速度和跟踪精度,由此提高了VICTS天线的跟踪效率。仿真实验结果表明,该算法有效地解决了跟踪速度和跟踪精度之间的矛盾,使天线能够快速、稳定和精确地跟踪卫星。 展开更多
关键词 可变倾角连续断面节阵列 天线 跟踪算法 跟踪效率
Dynamical control of directional nonlinear scattering from metallic nanoantennas by three-dimensional focal polarization orientation 认领
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作者 王湘晖 王建鑫 曾明 《光电子快报:英文版》 EI 2021年第2期65-69,共5页
We demonstrate that the directionality of far-field second harmonic(SH) emission generated from individual gold nanosphere can be flexibly engineered by manipulating three-dimensional(3D) focal polarization orientatio... We demonstrate that the directionality of far-field second harmonic(SH) emission generated from individual gold nanosphere can be flexibly engineered by manipulating three-dimensional(3D) focal polarization orientation of the excitation field, which is explained by the coherent interference between SH dipolar and quadrupolar emission modes. The SH dipolar emission mode is independent of the polarization direction of the fundamental field whereas the evolution of the focal polarization orientation can dramatically modify the quadrupolar emission pattern. Therefore, the resultant SH emission pattern has a polarization-dependent behavior and side scattering almost perpendicular to the propagation direction of the incident light can be observed under a specific condition. Our findings provide a novel degree of freedom for all-optical control of directional nonlinear scattering from single nanoantenna, thereby opening new possibilities for future potential applications. 展开更多
关键词 POLARIZATION SCATTERING antenna
Design of Ellipse Antenna Array for Cellular Phone Localization Systems 认领
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作者 Ahmad El Sayed Ahmad Jean-Marie Floc’h +1 位作者 Alaa Choumane Philippe Morgand 《无线工程与技术(英文)》 2020年第2期13-22,共10页
This paper describes our contribution in the ANR (Agence Nationale de la Recherche) project called GELOCOM (GEo-LOCalisation de telephOnes Mobiles) managed by the THALES Communications company, dedicated to the emerge... This paper describes our contribution in the ANR (Agence Nationale de la Recherche) project called GELOCOM (GEo-LOCalisation de telephOnes Mobiles) managed by the THALES Communications company, dedicated to the emergency localization of cellular phones. This contribution takes place in the field of antennas, with the development of broad-band systems: a circular array of six elements with separated outputs for the receiving part. In this paper, we present the design and the characterization of broad-band double ellipse array antenna. This special structure is chosen in order to obtain a good omnidirectional radiation pattern, enhance the gain and maximize the V/H polarization ratio. In comparison with the already existing antenna systems in the wireless market for similar purposes, the proposed antenna has considerably shown better performance which makes it competitive among other antenna models. For the design and optimization of antennas, we use CST MWS software. The antennas have been designed and successfully measured. 展开更多
关键词 Broad-band Antenna Double Ellipse Antenna Planar Monopole Antenna El-liptical Antenna Omnidirectional Radiation Pattern
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Submillimeter wave communication versus millimeter wave communication 认领
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作者 Madhuprana Goswami Hyuck M.Kwon 《数字通信与网络:英文版》 2020年第1期64-74,共11页
This paper studies the performance of a submillimeter wave antenna operating between frequencies 0.1 THz and 10 THz with a 4-cyano-4-pentylbiphenyl[5CB]substrate.Since the size and shape of the antenna impact its gain... This paper studies the performance of a submillimeter wave antenna operating between frequencies 0.1 THz and 10 THz with a 4-cyano-4-pentylbiphenyl[5CB]substrate.Since the size and shape of the antenna impact its gain/directivity,resonant frequency,bandwidth,and efficiency,the two antenna types considered in this paper are:(a)Rectangular Patch Antenna(RPA),and(b)Cylindrical Dielectric Resonator Antenna(CDRA).Here a submillimeter wave antenna is compared with a millimeter wave(a few GHz to 100 GHz)antenna.These popular mmwave antennas are chosen for the submillimeter wave antenna in order to understand changes in their performance as the result of changes in their geometrical shape.FEldberechnung bei Korpern mit beliebiger Oberflache(FEKO)software is used for the design and calculation of the Three-Dimensional(3D)ElectroMagnetic(EM)patterns.This paper also concentrates on the design and analysis of a massive submillimeter wave Multiple-Input Multiple-Output(MIMO)(8 by 8)RPA and CDRA. 展开更多
关键词 SUBMILLIMETER WAVE ANTENNA MILLIMETER WAVE ANTENNA Rectangular MICRO-STRIP patch ANTENNA Cylindrical dielectric RESONATOR ANTENNA Massive SUBMILLIMETER WAVE MIMO ANTENNA Applications
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A Wideband Circularly Polarized Jeans-Based Antenna at 2.45 GHz 认领
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作者 Miroslav Joler Anamaria Koloni? Maja Boljkovac 《天线与传播(英文)》 2020年第1期1-18,共18页
Development of textile antennas is an important segment towards the goal of creating smart clothing. In this paper, we report on a jeans-based circularly polarized textile antenna designed for the E-band (around 2.45 ... Development of textile antennas is an important segment towards the goal of creating smart clothing. In this paper, we report on a jeans-based circularly polarized textile antenna designed for the E-band (around 2.45 GHz). We present three variations of the design and the respective results. The antenna comprises a multi-layer jeans-fabric as the substrate, a conductive fabric as the patch, which is concealed with another layer of jeans, and the ground plane is formed by either a cooper foil or another conductive fabric. A multi-layer structure was chosen to provide a wider bandwidth and better efficiency, whereas the upper surface of the antenna was covered by one more layer of jeans to both make the antenna less conspicuous, when worn on the arm, and protect the patch and substrate from mechanical damages and moisture. All three variants are characterized by a good realized gain of about 3 dB, a wide beam width and a wide bandwidth of 21% or better, around 2.45 GHz, having the radiation efficiency around 36%, and front-to-back ratio of 5 dB or better, with the ground plane being just slightly larger than the patch. 展开更多
关键词 Textile ANTENNA Circular POLARIZATION Jeans-Based ANTENNA Probe FEED
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Multibeam Antenna Based on Butler Matrix for 3G/LTE/5G/B5G Base Station Applications 认领
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作者 YE Lianghua CAO Yunfei ZHANG Xiuyin 《中兴通讯技术:英文版》 2020年第3期12-19,共8页
With the rapid development of mobile communication technology and the explosion of data traffic,high capacity communication with high data transmission rate is urgently needed in densely populated areas.Since multibea... With the rapid development of mobile communication technology and the explosion of data traffic,high capacity communication with high data transmission rate is urgently needed in densely populated areas.Since multibeam antennas are able to increase the communication capacity and support a high data transmission rate,they have attracted a lot of research interest and have been actively investigated for base station applications.In addition,since multi-beam antennas based on Butler matrix(MABBMs)have the advantages of high gain,easy design and low profile,they are suitable for base station applications.The purposes of this paper is to provide an overview of the existing MABBMs.The specifications,principles of operation,design method and implementation of MABBMs are presented.The challenge of MABBMs for 3G/LTE/5G/B5G base station applications is discussed in the end. 展开更多
关键词 multi-beam antenna base station application Butler matrix wideband antenna multi-band antenna
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基于基片集成波导馈电的Ka波段渐变缝隙天线设计 认领
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作者 郝宏刚 李江 +1 位作者 张婷 阮巍 《电子与信息学报》 EI CSCD 北大核心 2020年第3期582-588,共7页
在被动毫米波(PMMW)成像焦平面阵列(FPA)馈源的天线中,直线渐变缝隙天线(LTSA)相对于传统的喇叭天线、介质棒天线具有其独特的优势。该文优化设计了一种新型的对跖直线渐变缝隙天线(ALTSA),通过加载超材料结构使天线的增益得到了改善,... 在被动毫米波(PMMW)成像焦平面阵列(FPA)馈源的天线中,直线渐变缝隙天线(LTSA)相对于传统的喇叭天线、介质棒天线具有其独特的优势。该文优化设计了一种新型的对跖直线渐变缝隙天线(ALTSA),通过加载超材料结构使天线的增益得到了改善,天线采用基片集成波导(SIW)技术进行馈电。通过仿真与测试分析,该天线在较宽的频带内具有良好的阻抗特性、较低的副瓣电平及较高且平稳的增益,所设计的天线具有较小的口径宽度,在焦平面中易于组成较为密集的馈源阵列,以提高被动毫米波成像的空间分辨率。 展开更多
关键词 天线 被动毫米波成像 对跖直线渐变缝隙天线 基片集成波导
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A Multivariable, Two-Dimensional Plot of Electromagnetic, Electric Field and Seismic Information for the Characterization of Earthquake Precursors 认领
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作者 John Ricken Wright 《地质学期刊(英文)》 2020年第3期213-234,共22页
Removal of the electrical shielding from a type of Fourier transform seismometer overlays seismic information with Extremely Low Frequency-range (ELF) electromagnetic signals between about 0.3 Hz and 36 Hz (the ITU-de... Removal of the electrical shielding from a type of Fourier transform seismometer overlays seismic information with Extremely Low Frequency-range (ELF) electromagnetic signals between about 0.3 Hz and 36 Hz (the ITU-designated range of ELF is 3 to 30 Hz). The observed signals originate in the electric power grid, shown clearly by the fact that they are sum and difference heterodyne products with the power grid’s higher harmonics of 60 Hz, typically the 36th and 37th, because the seismometer’s chosen frequency modulation (FM) carrier frequency is roughly 2200 Hz. It is especially interesting that on 2017-03-19, prior to 14:25:12 UTC, the instrument recorded an 11 minute sequence of 20.3 Hz ELF outbursts that culminated intimately with a 3.2 magnitude earthquake located a few miles west of Bardwell KY. These ~20.3 Hz ELF signals, very near the third Schumann resonance frequency, have been recorded numerous times. They are distinctive and fairly strong, ranging 15 to 30 db or more above the noise floor, but definitely not an every-day event;months can pass without them. So far most of these ELF signals do not have an intimately associated earthquake, with the event of 2017-03-19 being one of only two exceptions recorded thus far. That quake’s location was more than one hundred miles from the instrument, in the New Madrid Seismic Zone (NMSZ). The second case, a quake in Kansas, was about three times farther from the instrument, and its ELF signals were correspondingly weaker. Those other, unassociated electromagnetic events might come from quakes too weak to detect, but it should be noted that stronger, easily detected quakes also rarely exhibit any ELF/seismic “connectivity”. This paper describes an instrument that overlays ELF, electric field and seismic signals. The instrument’s two-dimensional (2D) output has a time axis (horizontal) resolution of ~3 seconds and an ELF frequency (vertical) resolution of ~0.3 Hz. 展开更多
关键词 Seismoelectromagnetics Premonitory Connectivity ~20 Hz ELF Power Grid as Antenna FM SEISMOMETER MULTIVARIABLE Display Electric Field ROSETTA Stone
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