A Constant Gain and Miniaturized Antipodal Vivaldi Antenna for 5G Communication Applications

This paper proposes a stable gain and a compact Antipodal Vivaldi Antenna (AVA) for a 38 GHz band of 5G communication. A novel compact AVA is designed to provide constant gain, high front to back ratio (FBR), and very high efficiency. The performance of the proposed AVA is enhanced with the help of a dielectric lens (DL) and corrugations. A rectangular-shaped DL is incorporated in conventional AVA (CAVA) to enhance its gain up to 1 dBi and the bandwidth by 1.8 GHz. Next, the rectangular corrugations are implemented in CAVA with lens (CAVA-L) to further improve the gain and bandwidth. The proposed AVA with lens and corrugations (AVA-LC) gives a constant and high gain of 8.2 to 9 dBi. The designed AVA-LC operates from 34 to 45 GHz frequency which covers 38 GHz (37.5 to 43.5 GHz) band of 5G applications. Further, the presented AVA-LC mitigates the back lobe and sidelobe levels, resulting in FBR and efficiency improvement. The FBR is in the range of 12.2  to 22 dB, and efficiency is 99%, almost constant. The AVA-LC is fabricated on Roger’s RT/duroid 5880 substrate, and it is tested to verify the simulated results. The proposed compact AVA-LC with high gain, an improved FBR, excellent efficiency, and stable radiation patterns is suitable for the 38 GHz band of 5G devices.     

70 m天线俯仰扇齿组合的加工与安装

俯仰扇齿组合是70 m天线结构系统的关键部件,其加工与安装的精度直接决定天线俯仰运动的精度,最终影响天线的指向精度。文中从俯仰扇齿组合施工现场保精度安装需求出发,介绍了俯仰扇齿组合前期生产加工、检测及预组装的详细工艺策划方案。通过设计合理的工艺检测基准、安装基准、工艺模板及工艺复位工装,解决了俯仰扇齿组合安装、检测及定位问题,最终安装精度达到了70 m天线俯仰扇齿组合的设计精度要求,为70 m天线结构系统现场顺利安装奠定了坚实的基础。     

一种小规模超宽带相控阵天线设计

目前基于阵元间强耦合效应已设计出超宽带相控阵天线,但是其规模较大。针对规模小或者在扫描方向上规模小,如何增强阵元间耦合而实现超宽带相控阵天线的问题,采用平衡对踵Vivaldi天线(BAVA)作为天线单元,优化天线单元辐射金属的形状,并采用镜像法布阵天线单元设计出一个小规模4×16的斜极化超宽带相控阵天线。仿真和试验结果表明,采用的方法可以增强小规模超宽带相控阵天线的阵元间耦合效应,实现频率0.8f0~2.0f0驻波比小于2,法向增益达17.34~23.0 dBi,在±45°范围内实现无栅瓣扫描。该小规模超宽带相控阵天线已在实际工程中应用。     

Multi-Reconfigurable Band-Notched Coplanar Waveguide-Fed Slot Antenna

This paper proposes an antenna design concept to achieve a multi-reconfigurable band-notch antenna by using a set of microswitches. The proposed idea was proved by the design of the coplanar waveguide (CPW)-fed slot antenna. The sample design gives a wideband antenna the impedance bandwidth of which covers the frequency ranged from 1.9 GHz to 6.55 GHz. The antenna could be configured to work either in single-band mode or in one of the defined dual-band modes.     

PCB Base Log-periodic Antenna for Mobile Communications

A log-periodic antenna can provide directivity and gain when operating in a wide band. The log-periodic antenna is used in many applications where wide bandwidth is required along with direct and medium gain. This research implements a sequential approach to the design and simulation of the performance of a printed log-periodic dipole antenna (LPDA) capable of operating in the 1800 MHz frequency range. The advantage of this antenna is the compactness and easy integration into planar circuits suitable for applications requiring wide bandwidth and high gain. The dimension of the designed antenna was originally calculated taking high frequency as 1885 MHz and low frequency as 1805 MHz, then modeled using HFSS-13 electromagnetic simulation to determine the effect of substrate dielectric properties on dipole width and length for element optimization. The design was verified by creating and measuring S11 and radiation dia-grams. The designed antenna has a total gain of 7.9dB and a wide bandwidth.     

浅析“动中通”在马拉松赛事中的技术保障与实践

“动中通”是移动卫星通信的简称。“动中通”在马拉松比赛的直播过程中起着非常重要的作用,在直播前期对“动中通”的运行路线、视音频信号的编码链路、卫星上行链路、天线伺服系统等各个环节都要进行全方位的测试与维护,总结出了一些行之有效的应对影响信号传输的技术方法,确保马拉松比赛直播信号优质安全的呈现在电视荧幕上。     

雷电对中波天调网络影响的模拟实验研究

针对雷电波所具有的非周期性、不确定性、强度大、危险性大等特点,通过实验的手段观测天调网络防雷的过程和衰减效果一直是业内的难题,研究了中波天调网络防雷作用的基本原理,提出了一种新型的可观测网络防雷效果的实验方法,并模拟了雷电对中波天馈线阻抗调配网络影响的表现形式和特点,揭示了雷电激发天调网络产生LC自由振荡的客观事实和普遍规律,解释了对振荡电压的衰减原理。实验表明,提出的实验方法既可用于网络防雷效果的观测研究,也可以用于防雷网络设计和调试结果的检验。     

高增益低副瓣X波段宽带圆极化Vivaldi天线阵设计

设计了一种新型的覆盖X波段的宽带圆极化2×2天线阵,具有高增益、低副瓣和良好的圆极化性能.该阵列以Vivaldi天线为基本单元,采用旋转对称的十字形结构,四端口等幅馈电且相位依次为0°,90°,180°和270°.此天线阵在整个X波段内阻抗匹配良好,轴比均低于3dB.采用矩形栅栏和底部扼流环结构将天线地板上的表面电流集中在槽线附近并降低后向辐射,从而获得低副瓣和高增益.频段内的峰值增益为10.7 dB,前后比大于20 dB.两个主平面的方向图对称性良好且基本重合.各天线单元间的低耦合使得天线阵的交叉极化很低.实物测试结果与仿真结果基本吻合.     

TD-LTE和LTE FDD融合组网天馈部署策略研究

从覆盖能力和站址空间的角度对LTE与3G系统共站址部署的可行性进行了分析;在对LTE FDD采用2T4R和多标准基站问题分析的基础上,分析了基于多标准基站的LTE融合组网天馈建设方案,给出了TD-LTE和LTE FDD融合组网条件下的天馈部署策略。     

活性酯固化环氧基高介电常数覆铜板的研制简

当前各界对于天线设计的重点在于小型化、结构简单化及多频或宽带。高介电常数基板可以缩小微波辐射波长,达到天线小型化的目的。采用活性酯作为环氧树脂的固化剂,活性酯固化剂分子中有两个或多个具有较高活性的酯基,可以同环氧树脂进行固化反应。在同环氧树脂反应时形成不含仲醇羟基的网架,所以固化后的环氧树脂具有低的介电损耗和吸水率。采用高介电常数填料作为功能填料。研制的高介电常数覆铜板具有低的热膨胀系数、低的介电损耗和低的吸水率。