一种宽带多网组合卫星导航终端天线

为了满足多系统兼容、高集成度卫星定位终端对天线的需求,提出了一种宽带多网组合卫星导航终端天线。天线采用宽带交叉偶极子结构实现全球卫星导航系统全频段(1 164 MHz～1 278 MHz&1 557 MHz～1 612 MHz)覆盖,采用平面倒F天线结构实现蓝牙/WLAN频段(2 400 MHz～2 483.5 MHz)覆盖,采用缺陷地单极子结构实现移动通信宽频(824 MHz～960 MHz&1 710 MHz～2 690 MHz)覆盖,通过微带枝节匹配和去耦结构等手段实现多组天线的融合,天线整体尺寸为120 mm×120 mm×45 mm。实测结果表明：天线电压驻波比优于目标带宽,方向图增益实测结果与仿真结果吻合。该天线具有频带宽、增益高、易调谐等优点,可较好地应用于全频段全网通测量型卫星定位终端设备中。     

一种全面屏智能手机天线设计

提出一种适合在全面屏手机终端上使用,带宽为700~960 MHz、1 710~2 170 MHz、2 500~2 700 MHz的手机天线.设计的手机仿真模型的长宽高尺寸为158 mm×77 mm×7.5 mm,手机天线的长宽高尺寸为70 mm×5 mm×4 mm,其天线效率分别为20%~35%（700~960 MHz）、20%~55%（1 710~2 170 MHz）、25%~35%（2.5~2.7 GHz）.在目前全面屏天线净空区域3.5 mm的情况下,天线的辐射效率能够满足设计要求.     

多层微带贴片天线单元和阵列设计

该文通过结合经验公式和全波分析法,设计了一种电容补偿双层贴片、四层介质的微带贴片天线单元,该单元天线在频率为995～1125MHz的范围内,在驻波比SWR1.5的情况下,相对阻抗带宽达到12.26％的工程要求。此外,该文给出由该单元天线组成的216天线阵以及天线阵的驻波比的实测结果,最后给出天线阵的各单元排列方式和单元之间的互耦特性曲线的实测结果。     

用于TD-SCDMA终端的新型倒F双频天线

本文设计并制作了一种工作于TD-SCDMA频段的新型倒F天线,该天线采用空间曲折、加载容性垂直寄生单元等技术实现了双频工作,其工作频带涵盖了我国自主研发的TD-SCDMA通信技术标准所使用的1 88～1 920MHz和2010～025MHz两个频段.该天线尺寸仅38mm×mm×7mm,满足终端天线小型化、结构简单和双频工作的要求.     

信号源内置式球形偶极子天线

为实现30 MHz～1 GHz频率范围内的机箱机柜电磁屏蔽效能测量,研制了直径为100 mm的信号源内置式球形偶极子天线.该天线采用具有陡峭上升沿与下降沿的30 MHz方波信号作为信号源,信号源和电源部分均置于天线内部.对天线幅值动态范围的测试结果表明:在与接收天线相距1 m的条件下,该天线在30 MHz～1 GHz频率范围内的动态范围都在50dB以上,大多数谱线的动态范围达到60dB.所研制天线体积小、可连续工作5小时以上,解决了体积较小机箱机柜的电磁屏蔽效能测试难题.     

缝隙加载双频RFID读写器天线设计

设计了一款应用于RFID系统的双频读写器天线,该天线由一层双边开槽贴片,厚空气层及接地层的加载缝隙耦合实现双频工作.仿真天线的性能指标为:在驻波比小于2.0时,低频段(900 MHz)的工作带宽约为70 MHz(870～940 MHz),天线增益为6.57 dBi,高频段(2.4 GHz)的工作带宽约为300 MHz(2.235～2.535 GHz),天线增益为4.74 dBi;所设计的天线尺寸为179.3 mm×120 mm.     

顺序旋转馈电背腔圆极化天线阵列

主要描述了一种基于顺序旋转馈电网络构成的背腔式缝隙圆极化天线阵.天线单元是一种低轮廓的背腔共面缝隙天线,包括运用介质填充的金属背腔和共地共面波导构成的馈电单元.该天线单元带宽为170 MHz,最大增益为5.7 dBi,其厚度小于λ0/50.而天线阵采用2×2天线单元顺序旋转馈电的方法来实现圆极化,其阻抗带宽和3 dB轴...     

230 MHz无线专网小型化平板天线设计

提出了一种用于电力230 MHz无线专网的平板天线,天线工作频率228～237 MHz,相对带宽3.9%。该天线由单层1 mm厚度FR4印制板的倒F结构辐射体组成,天线整体尺寸300 mm×260 mm×1 mm。天线通过匹配传输结构将馈电点放置于辐射体背部,便于安装。经过仿真天线增益性能良好,水平全向增益1.5 dBi,电压驻波比优于2。设计的天线经过微波暗室实地测试,测试结果与仿真结果吻合。     

人工神经网络基双频RFID读写器天线设计

给出了结合人工神经网络进行双频RFID读写器天线的优化设计方法,该天线由一层双边开槽贴片,厚空气层及接地层的加载缝隙耦合实现双频工作.以天线电磁仿真结果作为人工神经网络模型的训练数据,以天线贴片的四个关键结构尺寸作为神经网络模型的输入参数,以天线回波损耗作为输出参数,实现天线的快速优化设计.所设计天线的性能指标为:在驻波比小于2.0时,低频段(900 MHz)的工作带宽约为70 MHz(870～940 MHz),高频段(2.4 GHz)的工作带宽约为300MHz(2.235～2.535 GHz);天线尺寸为179.3 mm×120 mm.神经网络模型和电磁仿真结果吻合良好.     

一种用于手持移动终端的九频段平面印制天线

提出了一种应用于手持移动终端的九频段平面印制天线,该天线结构紧凑,尺寸为20 mm×28 mm×0.8 mm.利用弯折单极子、寄生地枝和耦合分枝激励起了五个谐振模式,并通过三个调节片和位于馈电点附近的阶梯形过渡结构改善了各个谐振模式的阻抗匹配,从而拓展了天线的工作带宽通过分析该天线关键参数对带宽性能的影响,对关键参数进行了优化,得到了满足性能要求的天线结构.天线样品的实测-6 dB阻抗带宽为700～1 008 MHz和1 692～2 984 MHz,覆盖了LTE700/2300/2500,GSM850/900,DCS/PCS/UMTS和2.4-GHz WLAN频段;工作频带内具有良好的辐射性能     

一种应用于5G的紧凑型阵列天线设计

提出一种应用于5G的紧凑型阵列天线,由4个天线单元相互正交放置,通过在天线单元之间的上下两个平面分别添加4个二分之一波长的微带线,提高了天线单元间的隔离度。利用高频电磁仿真软件,对所提天线单元及阵列结构进行分析。实验结果表明,阵列天线的工作频段分别为2.72~3.92 GHz和4.74~5.42 GHz,在工作频段内各天线单元间的隔离度均低于-20 dB,完全覆盖5G所需的3.3~3.6 GHz和4.8~5.0 GHz两个工作频段。该阵列天线结构紧凑,体积仅为68.5 mm×68.5 mm×1.524 mm,能够被5G的小型化便携设备所应用。     

一种5G手机的紧凑型16单元多频MIMO天线

提出一种应用于5G智能手机中结构紧凑的16单元多频段多输入多输出(MIMO)天线阵列。该多天线系统由8个紧凑天线阵列对组成,为了预留2G/3G/4G天线的布局空间,这8个天线阵列印刷在智能手机的两侧边上。每个天线阵列对由2个紧凑的间隙耦合环路天线组成,分别布置在系统板的上、下两侧;其中上侧天线工作在LTE band 46(5 150~5 925 MHz),下侧天线覆盖LTE band 42/43(3 400~3 800 MHz)。测试结果表明该天线阵列具有良好的阻抗匹配和隔离性能。同时还对MIMO一些包络相关系数进行了研究分析。最后研究了人手和头对整个天线性能的影响,仿真结果表明,在日常各种使用情况下,该天线阵列也具有良好的辐射特性。     

Compact and contact quad-band (DVB-H UHF/L, WLAN 11a/b) antenna for PMP applications

The quad-band antenna, which is composed of two compact dual-band antennas, is presented for potable media player (PMP) applications. The antenna for the broadcasting dual-band (DVB-H UHF; 470 - 862 - MHz, L; 1452 - 1492 - MHz) is composed of a planar inverted F-shaped antenna with an input matching circuit. The antenna for the communication dual-band (WLAN 11b; 2.4 - 2.5 - GHz, 11a; 5.15 - 5.8 - GHz) is composed of a folded dipole antenna with enhanced mutual coupling. The proposed antennas are contact with the PMP case (?_r = 3.2) which is used as a substrate for size reduction and compact design.     

Compact integrated diversity antenna for wireless communications

We introduce a compact integrated antenna that has two feed ports with more than 20 dB isolation between them. The significance of the design is that it can be utilized in compact wireless communication handsets to provide diversity signals or act as a duplexer allowing the receive and transmit signals to be well isolated. The antenna design is based on merging two patch antennas together in combination with capacitive loading so that a compact design can be obtained. Justification for the design is provided by considering the mutual coupling using the reaction principle and finite-dimensional time-domain (FDTD) simulations. Experimental results are also presented for a design that operates in the 2100-2200 MHz band for possible application in forthcoming third-generation wireless systems. Results include radiation patterns, S-parameters, and signal correlations between ports so that the diversity performance and isolation characteristics of the antenna can be demonstrated. These show that in typical wireless environments envelope cross correlations of less than 0.1 between the ports are obtained     

Triple band planar inverted F antennas for handheld devices

Two novel triple band planar inverted F antennas (PIFAs) are presented. The first antenna is realised by housing a dual frequency L-shaped spur line loaded PIFA element within the lower resonance PIFA element. The second antenna is realised by embedding two single element PIFAs within a quarter-wave patch. For both antennas, an isolation of better than -15 dB between the feed ports and a good agreement between simulation and measurement results was obtained     

Isolation Enhancement Between Two Closely Packed Antennas

This paper introduces a coupling element to enhance the isolation between two closely packed antennas operating at the same frequency band. The proposed structure consists of two antenna elements and a coupling element which is located in between the two antenna elements. The idea is to use field cancellation to enhance isolation by putting a coupling element which artificially creates an additional coupling path between the antenna elements. To validate the idea, a design for a USB dongle MIMO antenna for the 2.4 GHz WLAN Band is presented. In this design, the antenna elements are etched on a compact low- cost FR4 PCB board with dimensions of 20$,times,$40 $,times,$1.6 ${rm mm}^{3}$. According to our measurement results, we can achieve more than 30 dB isolation between the antenna elements even though the two parallel individual planar inverted F antenna (PIFA) in the design share a solid ground plane with inter-antenna spacing (Center to Center) of less than $0.095lambda_{o}$ or edge to edge separations of just 3.6 mm (0.0294 $lambda_{o}$). Both simulation and measurement results are used to confirm the antenna isolation and performance. The method can also be applied to different types of antennas such as non-planar antennas. Parametric studies and current distribution for the design are also included to show how to tune the structure and control the isolation.      

High-Efficiency Angled-Dipole Antennas for Millimeter-Wave Phased Array Applications

A high-efficiency microstrip-fed endfire angled-dipole antenna has been developed for millimeter-wave phased array applications. The antenna is built on both sides of a Teflon substrate (epsiv_r = 2.2) and this allows a wideband feed from the single-ended microstrip line to the differential dipole. The design results in wide radiation patterns for scanning purposes with a gain of around 2.5 dB at 20-26 GHz and a cross-polarization level of < -15 dB at 24 GHz. A mutual coupling of < -23 dB is measured between adjacent elements with 6.8 mm center-to center spacing (0.50-0.54 lambda₀ at 22-24 GHz). A variant of the angled-dipole antenna with a magnetic ground plane edge was also developed, and shows a measured gain of > 6 dB at 23.2-24.6 GHz and very low mutual coupling between elements (<-23 dB for a 6.8 mm spacing). Both antennas result in a radiation efficiency of > 93% when referenced to the microstrip line feed (including mismatch loss). The usefulness of these antennas as phased array radiators is demonstrated by several eight-element linear arrays at 22-24 GHz with scan angle up to 50 degrees. The application areas are in automotive radars and high data-rate communication systems.     

Extremely compact dual-band PIFAs for MIMO application

A MIMO structure consisting of two extremely compact planar inverted-F antennas (PIFAs) (λ/60 x (λ/20 x (λ/60) is proposed for GSM 900 MHz and 2.4 GHz wireless local area network applications. The miniaturisation of each antenna is achieved through a spiral-shaped PIFA and a capacitive load, forming a LC resonator. Both antennas have a good impedance bandwidth of 0.88?0.945 and 2.39? 2.48 GHz for 0.9 and 2.4 GHz band, respectively. The two PIFA antennas are polarised orthogonally to each other, and isolation better than 228 dB is achieved in both bands without any structure etched on the ground. The predicted results are compared with the measured data and good agreement is found.     

基于小间距低耦合阵元的微带天线阵设计*

设计微带天线阵时,减小阵元间距会导致阵元间耦合增加,从而导致增益下降(在考虑口径增益减小的基础上进一步下降).针对该问题,提出一种减弱小间距阵元间耦合的新方法,即通过在地板上蚀刻两条共面波导,引入新的幅度可调的耦合去抵消原有耦合,从而实现减小阵元间耦合的目的.该方法将邻边间距为0.024λ0(λ0是自由波长,中心间距约0.38λ0)的阵元之间的隔离度(IS21I)从6.1dB提高到21dB以上,改善了阵元的辐射特性,使每个阵元的辐射方向图接近单个贴片的辐射方向图.为验证有效性,本文基于该方法设计了一副二元微带天线阵,并对其进行测试,与等口径面的二元阵比较,增益提高了约1.2dBi,与等增益的二元阵比较,面积减少了约10.2％,且副瓣电平有较大改善.     

一种小型化的高隔离度UWB-MIMO天线

提出了一种紧凑、高性能、形状新颖的具有高隔离度的超宽带多输入多输出(ultra-wideband multiple-input multiple-output, UWB-MIMO)天线. 天线由两个圆形辐射元件组成,享有共同的类F形接地平面,尺寸为30 mm×18 mm. 在天线的接地平面中引入类F形短截线,在MIMO天线元件之间产生高度隔离. 所设计的UWB-MIMO天线具有极低耦合(S₂₁9.98 dB),适用于便携式通信设备.