采用螺旋线实现高隔离度的车载多频宽带MIMO天线

为解决车载天线工作带宽窄和MIMO天线低频段隔离度低等问题,提出一种应用于车载通信系统的多频宽带高隔离度的MIMO天线,其工作频段为824～960 MHz和1 710～6 000 MHz,可覆盖民用移动通信的2G/3G/4G/5G和无线局域网/车联网等频段。单极子天线单元采用弯曲、开槽等诸多技术实现多频宽带,还通过添加接地枝节来降低天线高度和提高物理稳定性;在MIMO天线设计上采用螺旋线来提高天线单元之间的隔离度。实测结果表明,天线在工作频段内的反射系数小于-10 dB,隔离度小于-20 dB,低频段增益和辐射效率略低,中高频段的增益均大于4 dBi,最高达到7 dBi,效率均高于70%,最高可以达到96%。实测数据与仿真数据具有良好的一致性,所研制的天线可满足车载天线对多频段通信和高隔离度MIMO天线的技术要求,其结构和尺寸专为安装于汽车内部中控台背面而设计。     

一种共面波导馈电的缝隙型超宽带天线

针对超宽带通信系统,提出一种小型超宽带天线,可以应用于终端设备。天线类型为共面波导馈电的缝隙型,缝隙结构为一矩形与一圆形组合而成,馈电结构与缝隙结构相似。天线的面积为22 mm×27 mm,印刷在厚度为0. 5 mm的FR4衬底上. 通过软件仿真分析了天线的工作原理以及尺寸对带宽的影响,仿真结果显示天线的带宽在不同的衬底厚度下均能覆盖UWB频段。天线的测试带宽为2.4 GHz~14.4 GHz,在超宽带的工作频段内测试效率超过76% ,测试增益大于2.1 dBi。     

一种单层贴片式双频双极化滤波天线

设计了一种单层式跨频段双频双极化滤波天线。该天线在同一平面上的高频低频辐射贴片共用一个馈电端口,且均可以在两个垂直方向馈电实现交叉方向的线极化辐射。该天线通过在馈电点与低频辐射贴片之间插入一个低通滤波器,明显提高了高频辐射贴片的交叉极化隔离度。研究结果表明,带滤波结构的天线在两个频率点的反射系数小于-20 dB,4.9 GHz的最大增益大于4.8 dBi,26 GHz的最大增益11.7 dBi,〖JP2〗两个辐射频率的辐射方向图均体现良好的线极化特性,且主极化比交叉极化大20 dBi。该天线可作为未来微波与毫米波共用的5G通信终端天线或5G通信基站的MIMO天线阵元,相关技术和结论对于研制一体化集成的双频交叉极化相控阵天线也有重要参考价值。     

一种用于笔记本电脑的双频段八天线系统

提出了一种应用于笔记本电脑的双频段八天线系统.该八天线系统由一个四天线系统、两个双天线系统和两个T形谐振带构成.在分析了四天线系统和两个双天线系统的耦合机理后,提出了减小耦合的方法.实测结果表明:天线样品在2.4-GHz无线局域网(Wireless Local Area Network,WLAN)频段的-10 dB公共阻抗带宽为90 MHz(2.4～2.49 GHz),在5.2/5.8-GHz WLAN频段的-10 dB公共带宽为0.9 GHz(5.15～6.05 GHz),其中在5.15～5.19 GHz频段内的反射系数为-9.5～-10dB;八个天线单元在2.4/5.2/5.8-GHz WLAN频段内的互耦均低于-15 dB;在2.4-GHz和5.2/5.8-GHz WLAN频段内的增益分别高于2.7 dBi和3.3 dBi、效率分别高于53％和65％.根据实测三维辐射方向图计算了八天线系统的包络相关系数.     

应用于物联网MIMO天线的双频谐振解耦结构

提出了一种用于双频MIMO天线的谐振器去耦结构。通过双频单极子MIMO天线对该解耦结构进行验证。双频单极子天线分别工作在低频2.4GHz和高频5.8GHz。 双频解耦结构在低频段主要是采用两个反向的π型微带谐振器解耦,高频段主要是采用π型缝隙谐振器解耦。天线采用微带线馈电,解耦谐振器与天线地板印刷在PCB同一面,结构紧凑易于与系统集成,可以广泛应用于物联网通信系统中。 实测结果：双频谐振器去耦结构实现隔离度高于22dB,单极子天线阻抗带宽分别为2.0GHz-3.0GHz和5.0-6.0GHz（S11<-10dB）,低频段增益最大增益点1.5dBi,高频段最大增益点3dBi。     

一种宽频带高增益16单元微带天线阵设计

设计了一个中心频率为6.52GHz具有宽频带高增益特性的16单元微带天线阵。综合运用H型缝隙耦合馈电技术、插入空气层技术和在贴片天线上切角的方法展宽天线的带宽。该天线阵由两层介质板构成,采用反相馈电可抑制高次模的耦合,交叉极化电平低。使用三维电磁场仿真软件AnsoftHFSS对该天线阵进行仿真优化,并根据仿真结果做成实物加以验证。对实物的测量结果表明:天线阵仿真阻抗带宽(S11≤-10 dB)为21.5%,增益为19.85 dB;实测阻抗带宽(S11≤-10 dB)为22.5%,增益为18.8 dB。天线阵性能良好,能满足工程实际要求。     

基于紧耦合结构的宽带基站天线设计

随着5G移动通信频段的公布,传统基站天线已不足以覆盖其工作频段。文章以紧耦合阵列天线理论为基础,提出了一种基于紧耦合结构的交叉偶极子宽带基站天线。该天线由两对正交的领结状偶极子天线构成,通过两对交叉偶极子之间的耦合效应,有效地展宽了天线的阻抗带宽。同时,通过在天线和金属反射板之间加载电阻型频率选择表面,吸收由反射板引入的谐振反射波,改善天线高频端辐射性能。仿真及测试结果表明:该天线在1.7-3.6 GHz 频率范围内,可以满足基站天线的设计指标,两端口驻波比均小于1.5,两端口之间隔离度大于55 dB,半功率波束宽度满足65°±5°范围,且整个频段内增益均大于8.5 dBi。     

一款面向5G微基站的双频双极化电磁偶极子天线的设计与分析

小型化是进行5G微基站天线设计的重要考虑因素,文中设计了一款适用于5G微基站的电磁偶极子天线. 天线由一对正交放置的单极化电磁偶极子、一对交叉放置的渐变式Γ形馈电线、一个圆形寄生贴片和一块正方形反射板组成,工作频段为2.50~3.62 GHz和4.8~5.0 GHz,能够覆盖工信部规定的5G的全部中频段. 在工作频带内,天线的输入回波损耗小于?10 dB;端口隔离度在低频段小于?25 dB,在高频段小于?42 dB;仿真平均增益在高、低频部分分别为5.57 dBi和9.84 dBi. 该天线能够实现双频段和双极化,可以作为小型化微基站天线设计的参考,同时为5G天线的商用化提供参考.     

基于耦合倒L加载法的WLAN双频印刷天线的设计

针对WLAN应用中多频段的传输要求和已有双频WLAN印刷天线存在的增益较小、带宽偏窄、尺寸偏大、回波损耗较高的问题,提出一种新的双频天线结构,即在传统倒F天线的基础上增加一个与之耦合的倒L枝节,从而得到可以覆盖WLAN频段且占用面积仅为35 mm×10 mm的双频天线。利用HFSS 13.0电磁仿真软件对天线参数进行仿真分析和优化。仿真结果表明,在2.4 GHz和5 GHz频段两个谐振点的S_(11)(回波损耗)分别低至-55.9 dB和-44.8 dB,最高增益分别达2.61 dBi和3.38 dBi,相对带宽分别为9.1%(2.40～2.63 GHz)和25.4%(5.15～6.65 GHz)。采用矢量网络分析仪对天线实物进行了测试,实测结果与仿真结果一致性良好,可以满足WLAN的需要。     

天线孔径共用技术研究

提出了一种新的天线孔径共用的方法。在低频单圆锥天线的辐射非敏感区上加载高频段微带天线阵,可以将两个不同频段和极化的天线集成为一个天线孔径,该天线的体积质量与原低频段天线相当,天线的两个馈电端口集成在原单圆锥天线的地板上。利用电磁仿真软件HFSS分析了该共用孔径天线的性能,在双频段0.7~1.3 GHz和4.1~4.2 GHz内反射系数均小于–10 dB,两个端口之间的隔离度大于31 dB,辐射方向图低频段为全向,高频段为定向,4.15 GHz增益达到11 dBi,仿真结果验证了该孔径共用方法的可行性。     

Dual-band polarization and frequency reconfigurable antenna using double layer metasurface

In this paper, a polarization and frequency reconfigurable antenna with double layer metasurface, responsible for frequency and polarization reconfiguration respectively, is proposed. This antenna could operate in linear polarization in 4 GHz and circular polarization in 5 GHz band. By rotating the frequency reconfiguration metasurface, the linear polarization (LP) operating frequency can be continuously changed from 4 GHz to 4.35 GHz (8.4%) with circular polarization operating frequency around 5 GHz unchanged. Moreover, polarization of the whole antenna at 5 GHz can be reconfigured to linear polarization (LP), right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP) by rotating polarization reconfiguration metasurface, the 3 dB axial ratio bandwidth is 5.0–5.2 GHz (4%). In all states, gain of the antenna achieves 5 dBi.     

Design of Dual‐Band MIMO Antenna with High Isolation for WLAN Mobile Terminal

In this paper, we propose a dual‐band multiple‐input multiple‐output (MIMO) antenna with high isolation for WLAN applications (2.45 GHz and 5.2 GHz). The proposed antenna is composed of a mobile communication terminal board, eight radiators, a coaxial feed line, and slots for isolation. The measured ?10 dB impedance bandwidths are 10.1% (2.35 GHz to 2.6 GHz) and 3.85% (5.1 GHz to 5.3 GHz) at each frequency band. The proposed four‐element MIMO antenna has an isolation of better than 35 dB at 2.45 GHz and 45 dB at 5.2 GHz between each element. The antenna gain is 3.2 dBi at 2.45 GHz and 4.2 dBi at 5.2 GHz.     

一种宽带双极化波导阵列天线的设计

设计了一种适用于雷达、通信等领域的宽带双极化波导阵列天线。天线的垂直极化信号通过波导阻抗变换直接馈电实现,水平极化信号通过由垂直极化信号馈电、缝隙耦合的方式实现。设计的阵列天线在12 GHz～15 GHz的频带内驻波比小于2,交叉极化低于25 dB,单元增益在带内大于8 dB,波束宽度大于60°。加工天线后实测结果与仿真结果吻合,该种阵列天线既适合固定波束阵列天线,又适合具有相扫功能的阵列天线。     

2．55～17GHz小型化圆锥天线

提出一种新型的超宽带全向电小天线,应用折叠技术改变了地板的形状,极大地减小了天线的物理尺寸,方便了实际工程中的安装和携带。设计的天线工作频段为2．55～17GHz,电压驻波比小于2,在频段7～17GHz增益5dBi左右,低频段增益有所下降,但仍大于1dBi。设计过程中,根据频率无关天线（单锥天线）的物理尺寸,通过仿真软件CST建立模型,最后得到的尺寸为37．8mm×60mm。     

Cylindrical ring dielectric loaded horizontally polarized omnidirectional antenna for wideband radiation

A wideband horizontally polarized omnidirectional antenna with a cylindrical ring dielectric (CRD) loaded is proposed. Compared with the conventional alford-structure loop antenna (ASLA), the impedance and radiation pattern bandwidths are broadened by loading a CRD to the ASLA with two wing sections. The designed antenna is fabricated and measured, and good performance has been obtained. The measured reflection coefficient is less than −10 dB over the frequency band 1.63–2.8 GHz, i.e., 52.8%, which can cover 2G/3G/LTE band totally. The gain variation in all directions of horizontal plane is less than 1.4 dB in the whole band. The maximum gain is 1.56dBi throughout the operating band and it appears at 1.66 GHz. It is worth noting that the gain is around 1dBi and almost constant from 1.9 GHz to 2.7 GHz. Besides, the designed antenna has a compact size of 0.55λ × 0.55λ × 0.057λ, λ is for the lowest frequency of the operating band.     

一种宽带分形自互补单极子天线的设计

提出一种结合分形与自互补理论的新型宽带单极子天线。辐射部分由Sierpinski分形图案的金属贴片和互补的缝隙贴片印刷在FR-4 介质板上构成,由微带线经阻抗变换后馈电。分形技术的利用使得该天线实现了20%的尺寸缩减,自互补结构则大大拓展了天线的带宽,两者的结合使得该天线在保持平面结构的同时取得优良的性能。仿真与测试得到该天线在4.98-9.93 GHz 频带内反射系数小于-10dB,具有66.4%的带宽,带内增益在1.3-3.3dBi 之间。该天线具有平面、宽带、小型化的优点,在小型化通信系统中具有良好的应用前景。     

Dual‐Polarized Small Base Station Antenna Integrated RF Module Applicable to Various Cell Environments for Next‐Generation Mobile Communication Service

A small dual‐polarized base station antenna with a simple isolation patch is presented. A high isolation is achieved when using a shorted metallic isolation patch. The experimental results indicate that the measured impedance bandwidth of the proposed antenna is 1.72 GHz to 1.89 GHz for small cell systems and that the isolation is more than 30 dB. The proposed antenna exhibits good radiation patterns with a peak gain of 8 dBi.     

Broadband sub-6 GHz flower-shaped MIMO antenna with high isolation using theory of characteristic mode analysis (TCMA) for 5G NR bands and WLAN applications

A small size neutralization line integrated flower-shaped MIMO antenna is designed and analyzed for sub-6 GHz type 5G NR frequency bands like n79 (4400–5000 MHz), n78 (3300–3800 MHz), n77 (3300–4200 MHz), and WLAN (5150–5825 MHz) applications. The novel approach of theory of characteristic mode analysis (TCMA) is introduced to provide physical insight of the designed structure and its characteristics behavior. Due to the suggested modifications in the geometry, the isolation among the patches is greatly increased. The overall miniaturized dimension of the MIMO antenna is 25 × 40 mm². The edge-edge spacing among the elements is 0.0233λ. The prototype antenna is fabricated and measured that shows good agreement compared with simulated results. The designed MIMO antenna without the presence of decoupling structure offers an isolation of 28 dB, gain of 3.6 dBi, and radiation efficiency of 69.7% at the resonant frequency. The proposed MIMO antenna covers a broad range of frequency band from 3.296 to 5.962 GHz with −10 dB impedance bandwidth of 2666 MHz and maintains a good isolation of greater than 50 dB for the entire operating band. The tested radiation efficiency and gain are 85.3% and 6.22 dBi at 3.5 GHz. Moreover, the diversity parameters of the neutralization line integrated MIMO antenna, that is, channel capacity loss (CCL) isolation, mean effective gain (MEG), total active reflection coefficient (TARC) diversity gain (DG), and envelope correlation coefficient (ECC), are analyzed and discussed in this article.     

Design and fabrication of compact 2 × 2 dual linear polarized wideband and high gain array for Ku-band satellite communication application

In this paper, the design of a planar array antenna for two-way satellite communication is presented. The antenna unit consists of four elements and two waveguide feeding networks used to connect the elements. The radiating elements are small horn apertures. Each element of the array includes two separate ports to radiate vertical and horizontal polarization, respectively. The feeding networks consist of power dividers and bends to connect the vertical and horizontal polarization ports of horns, separately. Radiating elements and feeding networks are designed to cover receive band (10.5–12.75 GHz) and transmit band (13.75–14.5 GHz) within Ku-band. The maximum gain for this type of antenna is 21 dBi.