基于超材料结构的定频波束可调天线设计

提出了一种新颖的波束可调天线。该天线辐射单元采用加载电容的超材料结构,相较于传统波导裂缝阵列天线的辐射缝隙,超材料辐射单元的尺寸缩小了76%;天线采用蚀刻有超材料结构的Rogers RT5880印刷电路板(PCB)作为天线辐射面,通过调整加载在超材料单元上的电容来调整波束指向。天线的测试结果与电磁仿真软件仿真结果接近。测试和仿真结果表明,天线工作在频率15 GHz,最大增益为11 dBi,辐射效率为80.8%,波束可调天线实现了-28°,-20°,-12°,-6°,6°, 13°和24°七种不同波束指向。     

一种具有宽角稳定相位中心的双频段圆极化GNSS天线设计

本文介绍了一种在宽波束范围内具有稳定相位中心的双频段圆极化 GNSS(全球卫星导航系统)天线。天线设计为层叠空气腔式天线结构,采用幅度相等,相位相差 90°的四端口馈电方式,空气腔式天线在宽角范围内获得了较好的圆极化辐射特性。对称结构以及等幅等相差馈电的天线设计,可在宽角范围内获得较高的相位中心稳定度。测试结果表明:在四个导航频段内, 天线波束宽度大于±36°,±46°角域范围内的轴比小于 3dB,±70°角域范围内的相位中心稳定度小于 1.61mm,具备很强的工程应用价值。     

一种单层双频宽带GNSS测量型天线设计

基于单介质层结构,设计了一款双频宽带全球卫星导航系统(GNSS)测量型天线,天线采用单层高性能轻质复合材料作为双频微带天线共用的辐射介质基板。双频辐射贴片单元采用共面齿轮结构设计,并在天线单元外围设置一系列短路销钉来有效改善天线轴比带宽、低仰角辐射增益等参数,四馈点馈电技术和宽带耦合相移馈电网络的应用保证了天线相位中心稳定度更加可靠。设计结果表明,该双频天线单元大于等于5 d Bi的辐射增益带宽均大于245 MHz,高低频3 d B轴比带宽分别为-76°~76°和-116°~116°,低仰角90°增益滑落均小于11.5 d B,经实物样机对比测试分析,实测结果与仿真结果基本吻合。实测频谱显示,该天线工作频段覆盖目前在运行的四大导航系统全部工作频点,较好满足GNSS精确测量与定位系统终端设备应用需求。     

一种宽频带高稳定相位中心导航天线的设计

设计了一款基于阿基米德螺旋天线的宽频带高稳定相位中心导航天线.采用阿基米德螺旋天线结构实现了宽带驻波带宽和轴比带宽,结合三维扼流环结构改善了天线相位稳定度和多径抑制能力.通过有限元电磁仿真软件建立了仿真模型和完成了参数优化设计,所设计的宽带高稳定相位中心导航天线的指标达到:在GPS、北斗、GLONASS和Galileo卫星导航系统的所有工作频点上,输入端口驻波比均小于1.45;在俯仰角-60°~60°主波束范围内轴比小于3 dB,相位稳定度在-2.5°~2.5°,方向图增益均在5 dB以上.相比于未加载扼流环,所设计天线的增益前后比改善2~6 dB（仰角60°和仰角120°对应增益差值）.该研究表明,结合了三维扼流环结构的阿基米德螺旋天线综合性能优异,适于设计宽频带高稳定相位中心天线.     

双圆极化共形相控阵天线研究

设计了一种基于十字缝隙耦合双圆极化微带共形相控阵天线。首先设计了微带天线单元,分析了天线各结构参数对天线性能的影响。通过电桥向偏馈于十字缝隙上的馈线馈电,实现等幅、相差90°馈电,电桥的两个端口分别获得旋向相反的圆极化信号。然后对天线单元进行了测量,结果表明天线轴比小于3dB 的带宽为16%,驻波小于1.5 的带宽 为17%,波束宽度大于87°。最后对5×5 共形相控阵天线进行了仿真与测量,结果显示天线可以扫描60°,适合用作载体共形的卫星通信天线。     

一种新型的低雷达散射截面微带天线*

提出了一种减缩微带天线雷达散射截面(radar cross section,RCS)的新方法,该方法基于对微带天线表面感应电流的分析,给出可用于降低微带天线RCS的边缘结构。在参考天线的基础上,利用该方法设计了一款新型的低RCS微带天线。该设计天线与参考天线相比,具有同样的辐射性能。使用该方法后,参考天线在与水平面成小角度的平面波照射(掠入射)下,在4~12GHz的宽频带范围内,在φ=-45°~45°角域内的RCS平均值减缩了8.1d B。试验结果证明了该方法的有效性。     

A Novel Reconfiguration CPW Leaky-Wave Antenna for Millimeter-Wave Application

A novel reconfigurable millimeter-wave leaky-wave antenna is proposed according to the radiation characteristics of periodically loaded coplanar waveguide and simulated by the finite-difference time-domain method. The simulated results demonstrate that the single main beam of this antenna operating at 35.0GHz can scan with small steps in the E-plane from ?90° to 90° except the angle around 0°. The main beam scanning is obtained by the antenna structure reconfiguration with nine discrete states controlled by embedded switches and two feed ports. The antenna is useful for millimeter-wave applications.     

用于船舶自动识别系统的机载阵列天线设计

为了满足船舶自动识别系统抗干扰性能的要求,设计了一种机载阵列天线.天线阵列由5个单极子天线单元组成,整体尺寸为Φ720 mm×306 mm,天线单元沿圆周均匀排列.通过泰勒分布和牛顿优化算法,优化阵列的辐射幅度及相位,得到实测的方位面增益-15 dB抑制范围达到128°,-20 dB抑制范围达到77°;装机后-15 dB抑制范围在114°以上,-20 dB抑制范围在51°以上.该阵列天线结构简单,成本低,满足机载环境的使用要求.     

毫米波车地通信的小型化波导螺旋阵列天线设计

高速磁浮列车毫米波车地通信系统要求其车载天线具有小型化、宽频带、圆极化和辐射扇形波束等特点。为更好地满足这些要求,设计一种中心馈电的小型化波导螺旋阵列天线。该天线馈电系统采用同轴波导中心馈电、4路矩形波导并馈的形式,通过改变馈电波导尺寸、耦合探针长度以及末端采用波导同轴转换器等形式,实现了所有单元的等幅馈电;天线单元由低剖面螺旋天线构成,采用顺序旋转技术改善天线的圆极化性能。利用全波电磁仿真软件设计了一款中心频率为38 GHz的28单元波导螺旋阵列天线,并进行了实验测试。测试结果表明：在37~39 GHz频带范围内,天线驻波比小于1.41,增益大于21.7 dB,轴比小于3.6 dB,俯仰面波瓣宽度为4.5°~4.7°,方位面波瓣宽度为29°~29.7°,满足毫米波车地通信系统车载天线的设计需求。     

一种新型双频共形共孔径机载导航天线设计

本文阐述了共形天线的基本设计方法及其优点，设计研制了一种新型双频共形共孔径导航天线。该天线有两个射频输出端口，分别工作在 L 波段和 C 波段。通过分析对比不同形式的天线集成手段，最终提出一种性能优良的天线孔径综合实现方式并研制实物验证。仿真数据与实测结果基本吻合，在有效的工作频带和俯仰角为 60°~95°、方位角为-45°~45°的角域范围内， L 波段天线增益≥-1dB，C 波段天线增益≥-2dB。     

基于外场调制的方向图可控天线

该文设计了一款工作在2.45GHz并可实现60°扫描范围的方向图可控天线阵列。该天线阵列引入介电常数可控的铁电材料作为基板,通过外加直流偏置改变铁电材料的介电常数,从而实现单元馈电相位的连续变化。该天线阵列由馈电结构、隔直结构、移相器及天线阵元4部分组成,各部分分别集成在地板两侧的2个金属层上。不同于其他设计,该天线仅通过控制外加直流偏置电压的大小实现天线最大波束-30°~30°范围内的变化;此外,天线设计了一种新颖的直流偏置电路,减小了天线的设计复杂度,使设计的天线具有更高的实用价值。     

Scanning characteristics of ferrite fed microstrip array antenna

A new ferrite fed microstrip scanning array antenna is proposed which is capable of beam scanning in the azimuthal plane as well as in the elevation plane. The antenna consists of eight microstrip arrays, each having six elements in cascade. The antenna is fed with a ferrite loaded rectangular to circular waveguide transition. The coupling between the feed system and diOEerent arrays is achieved through slots cut in the circular waveguide. Theoretical investigations of the proposed antenna exhibit a beam scanning of ±180° in the azimuthal plane with the help of dc bias and 90° in the elevation plane for ±750 MHz deviation. A scan rate of 0:06° MHz^?1 is achieved for each array antenna in the elevation plane, which makes it suitable for radar. Continuous uniform beam shift is observed during scanning.     

5G毫米波有源阵列封装天线技术研究

提出了一种5G毫米波有源阵列封装天线.该阵列由8×16个微带天线单元组成,通过耦合式差分馈电,天线实现了宽带匹配和方向图高度对称特性.通过对天线与芯片进行合理布局,减小了芯片射频端口到天线子阵的馈电线损,提高了有源阵列天线的整体效率.测试结果表明,该阵列天线在工作频段为24.25～27.5 GHz的等效全向辐射功率(E...     

一种宽频带导航天线的研究与设计

研究并设计了一款基于阿基米德螺旋天线的宽频带(覆盖GPS,BeiDou 和GLONASS 卫星导航系统的所有工作频点,即1.1 -1.7 GHz)高稳定相位中心导航天线。以带有反射腔的阿基米德螺旋天线为基础,结合三维扼流环抑制多径效应的性能,通过加载扼流环,并经有限元电磁仿真软件的参数优化设计,很大程度上改善了整个频带内天线在特定俯仰角范围内的相位稳定度。所设计的宽频带高稳定相位中心导航天线的指标达到:在GPS,BeiDou 和GLONASS 卫星导航系统的所有工作频点上,输入端口驻波比小于1.5;在俯仰角为-60°-60°的范围内,方向图轴比小于2 dB,相位稳定度在-2.7°-2.7°;同时由于扼流环的加载,天线的抗多径性能也得到了改善。研究表明,加载了三维扼流环的阿基米德螺旋天线综合性能优异,适合作为宽频带高稳定相位中心导航天线。     

Peano分形加载单极子辐射性能的研究

对有限地板尺寸和介质填充情况下Peano分形加载单极子天线的辐射特性进行了研究.利用HFSS分析了地板尺寸和填充介质材料对天线反射系数、辐射方向图和增益的影响.仿真表明:随着地板尺寸的减小,天线的阻抗带宽和增益明显减小,H面方向图变化不大,而E面方向图的半功率波束宽度增大,波束仰角减小;填充材料的介电常数过大会导致天线性能的恶化.在分析研究的基础上,设计并研制了地板尺寸为220mm×220mm的一阶和二阶Peano分形加载单极子天线.天线分别实现了45°和36°的波束仰角,50°和45°的半功率波束宽度.仿真与实测结果均表明凋节地板尺寸是控制Peano分形加载单极子天线E面半功率波束宽度和波束仰角的一种简单而有效的方法.     

Hybrid Amplitude Control Antenna Array System for Energy Efficient W-CDMA Network with Adaptive Coverage and Capacity

This paper introduces a novel technique and mathematical formulation of two dimensional elastic footprint variations and adaptive sector configuration variations by using a hybrid adaptive amplitude control antenna array system. The antenna array system can control the elevation beam-widths from 6.84° to 13° and the azimuth beam-widths from 33° to 93° for obtaining the adaptive capacity and coverage. The work illustrates the application of the antenna array system in the energy efficient W-CDMA network. The antenna array half-power beam width variation is achieved by using the antenna array amplitude control and co-located multiple antenna array switching. The Node-Bs can adaptively switch to three, four, five, six and non uniform sector configurations with the antenna array beam width control and adaptive neighbor relations. Sector configurations will vary according to the pre-defined specific traffic loading percentages out of Node-B’s total channel capacity to reduce the energy consumption of the entire network. The paper introduces an adaptive footprint overlaps shifting technique, where the sector with less traffic load will expand its footprint towards the sector with higher traffic load and the sector with higher traffic load will shrink its footprint by maintaining a fixed footprint overlaps to improve the coverage and the capacity of the network. The footprints overlap shifting is applicable only for the active sector antennas facing each other. The results confirm that the proposed antenna array system outperforms the automatic tilt optimization and can control coverage, capacity and improve the energy efficiency of the W-CDMA network.     

Reconfigurable Beam‐Steering Antenna Using Dipole and Loop Combined Structure for Wearable Applications

This paper proposes a reconfigurable beam‐steering antenna using a bended dipole and a loop. The radiation patterns of the two antennas are cancelled or compensated, and headed towards a specific direction when the dipole and loop antenna are combined at a reasonable ratio. The proposed antenna can steer the beam directions by controlling the operation of two artificial switches. The proposed antenna was manufactured on a PCB (FR‐4) and a flexible PCB (polyimide). In the case of the antenna that was fabricated on a PCB, the maximum beam directions were +50°, 0°, and –50° in the azimuth direction using the two artificial switches, and the antenna gain was 1.96 dBi to 2.48 dBi in the operation bandwidth of 2.47 GHz to 2.53 GHz. Also, the antenna was fabricated on a flexible PCB and measured under various bending conditions for wearable applications.     

A novel miniature hexagonal shape switched pattern and frequency reconfigurable antenna

This proposed work introduces the structure of frequency and pattern reconfigurable patch antenna. This proposed design comprises of a hexagon patch antenna with four oblique slits, two longitudinal and two latitudinal slits. Four PIN diodes are used to enable frequency and pattern reconfiguration in the longitudinal and latitudinal slits. The operating frequencies of the proposed reconfigurable antenna are 4.25, 5.65, 6.8, and 8.2 GHz and have a pattern slope of ?30°, 0°, +30°, and 180°. The pattern is reconfigurable in four directions without any servo system. The designed antenna is fabricated, and its performance is proved using quantifications. Experimental results have less than 15% error with the simulated results. This antenna is used for C‐band applications.     

一种新型波束可控的口径耦合天线

设计一种基于人工电磁结构（AMC）的新型口径耦合天线。对加载了AMC 结构的口径耦合天线进行仿真。 根据仿真结果,天线的工作频率为5.5GHz,辐射的波束指向21°时增益为6.4dB。文中对天线的参数进行分析,波束 的偏移角度与AMC 结构的有关。将AMC 结构变为一排,天线波束可以指向11°。根据天线单元构造1×2 的子阵, 阵列天线具有更高的增益和带宽,并可以有波束的偏移。 天线子阵工作在5.5GHz 时天线的波束指向为26°,增益 8.47dB。     

Broadband multimode antenna and its array for wireless communication base stations

A wideband dual‐polarized antenna coupling cross resonator is proposed for LTE700/GSM850/GSM900 base stations. An additional resonance is introduced to obtain strong coupling between the dipole and resonator. Moreover, the input impedance of the proposed antenna is steadily close to 50 Ω, which results in better impedance matching. Therefore, a wide bandwidth can be achieved with multiresonance. A prototype is fabricated to verify the proposed design. The measured results show that the antenna has a fractional bandwidth of 35.7% from 690 MHz to 990 MHz for |S₁₁| < ?15 dB. Stable radiation patterns as well as gain are also obtained over the entire operating band. Moreover, a five‐element antenna array with an electrical downtilt of 0° to 14° is developed for modern base station applications. Measurement shows that a wide impedance bandwidth of 34.7% (690 MHz to 980 MHz), stable HPBW (3‐dB beamwidth) of 65 ± 5°, and high gain of 13.8 ± 0.6 dBi are achieved with electrical downtilts of 0°, 7°, and 14°.