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宽频带宽波束磁电偶极子天线设计 总被引:3,自引:0,他引:3
为了展宽天线的波束宽度,在磁电(ME)偶极子天线的基础上,该文设计出一种低交叉极化宽频带宽波束的新型磁电偶极子天线。通过将振子倾斜弯折,展宽了天线的波束宽度;结合6个寄生振子的对称加载,提高了辐射方向图的一致性。在型馈电结构基础上,优化天线的振子间距和振子长度,实现了天线58.5%的相对带宽(S11-10 dB),频带范围为2.3~4.2 GHz;对振子倾斜角度以及寄生振子的参数进行优化,在2.4~4.0 GHz的频带内实现了辐射方向图E面和H面同时达到120以上的半功率波束宽度(HPBW)。测试与仿真有较好的一致性,证明了所设计天线不仅具有宽频带宽波束特性,同时在整个频带范围内方向图的一致性得到了极大地提高。 相似文献
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小型化准分形加载单极子天线 总被引:6,自引:1,他引:5
提出了一种小型化宽带加载单极子天线,即对有顶部加载的单极子天线进行准分形和RLC集总加载.研究表明准分形可以有效地降低天线的谐振频率,提高辐射能力.准分形加载单极子天线和三维分形树单极子天线相比,结构非常简单,容易实现,和典型的加载单极子天线相比,天线的电尺寸要小得多.对准分形加载单极子模型天线进行了测试,实测结果和仿真结果比较一致.加入匹配网络后,可得到10:1的带宽. 相似文献
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设计了一种加载U型缝的小型化分形结构微带天线。该天线应用Giuseppe Peano分形理论和U型缝加载技术,延长电流的有效路径,从而降低天线的谐振频率,实现天线小型化,同时采用空气作为介质层,减小天线的Q值,增加天线带宽。通过使用HFSS对天线进行仿真优化,得到了天线尺寸参数。仿真结果表明,天线的相对带宽为6%(3.47~3.71 GHz),最大增益可达2.91 dBi,整体辐射性能良好。天线贴片尺寸仅为14 mm×14 mm,相比于普通微带天线,面积缩减了59%。该天线结构简单,尺寸小,能较好地适用于WiMAX通信。 相似文献
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设计出一种单馈小型化宽波束双层圆极化微带天线,通过选取低介电常数的介质基片,在双层圆形贴片上分别刻四个槽减小天线的尺寸,中心开十字缝增加天线的阻抗带宽,在贴片边切角和贴片的对角线上选择合适的馈电位置实现圆极化,天线尺寸减少37%,天线方向图对称性好,波束宽度大于80°,增益大于5.3 dB。 相似文献
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短波天线不仅要求超宽带(3~30 MHz),并且由于存在尺寸庞大的难题,对天线的小型化和结构简洁有苛刻要求.提出了一种金属线结构的新型单极子短波天线,结构简洁,通过分形辐射振子和T型馈电结构获得超宽工作频带和小型化性能,同时还能够调整天线姿态实现全向或定向辐射,以及一定程度上改变天线波束指向仰角.为验证设计的有效性,加... 相似文献
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地球覆盖波束天线为低轨卫星与地面终端之间的数据传输建立了通道,文中研究了一种新型的介质
加载地球覆盖波束天线。基于介质加载的方法,文中提出了一种圆极化地球覆盖波束天线设计,该天线由馈电网
络、馈源和介质三部分组成,介质包括底部圆柱部分和顶部半球部分,馈源集成于介质内部。设计的地球覆盖波束
天线工作在C 波段,轴向0°~64°范围内增益在0 dBic 以上,40°方向增益为5. 2 dBic。天线尺寸紧凑,辐射波束具有
较好的空间截止特性,可满足立方星应用。 相似文献
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针对宽波束天线在车载雷达中的应用,突破角雷达方位面3 dB波束宽度的限制,实现微带阵列天线在水平面的宽波束覆盖,设计了一款1×10串馈微带双层结构天线。线阵单元采用道尔夫-切比雪夫(Dolf-Chebyshev)综合法电流分布来达到降低天线俯仰面副瓣的效果,在串馈阵列上方加载寄生贴片和介质基板拓展天线方位面的3 dB波束宽度。分析了双层天线展宽波束的原理,加工并实测了双层宽波束天线,其方位面的3 dB波束宽度为134.6°,增益达到10.6 dB,副瓣电平为-19.8 dB,可以满足车载角雷达天线需求。 相似文献
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A switched parasitic monopole antenna on a finite ground structure with a conductive sleeve attached to a small, circular ground plane controls the vertical radiation direction. The antenna was designed using a genetic algorithm and finite element (FEM) solver. At 1.575 GHz, the constructed antenna exhibited a front to back ratio of 10.7 dB and gain of 6.4 dBi with no elevation from the horizontal. The switched parasitic nature of the antenna allowed it to steer a directional beam through 5 locations in the azimuth. Incremented from 0/spl lambda/ to 0.45/spl lambda/, the sleeve was observed to linearly depress the main lobe elevation with little influence on other antenna characteristics such as gain and S/sub 11/. 相似文献
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A novel ground-plane shape to improve the horizontal gain for electrically steerable passive array radiator (ESPAR) antennas is investigated. The peak directivity of a monopole antenna with a finite ground plane, such as a circular or rectangular ground plane is at a higher angle from the horizon. Thus, the horizontal gain is lower than that of a dipole antenna. Using a circular ground plane of a half-wavelength radius with a skirt of a quarter wavelength wound around it, the angle of the peak directivity and the horizontal gain for the ground-based communication system were improved. For an ESPAR antenna - one of the monopole arrays - the horizontal gain was also improved. It was confirmed that it was possible to form the main-beam radiation and a beam in the horizontal plane, each in an arbitrary direction, by changing the control voltage to the passive element. This was shown by an experiment with an ESPAR antenna with a finite reflector, a feed element, and seven passive elements. 相似文献
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Simulation results for a dual-band switched parasitic smart antenna array designed for cellular communications systems are presented. The array consists of six loaded monopole elements on an infinite ground plane and offers five switched directions equally spaced through 360°. At 900 and 1900 MHz, the 10 dB bandwidths are 15 and 13%, respectively. The antenna covers the azimuth plane with a maximum gain of 4 dBi and a minimum gain of 2 dBi. The front-to-back ratios of the radiation patterns are better than -15 dB. The design is robust in terms of manufacturing and environmental tolerances 相似文献
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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. 相似文献
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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。 相似文献
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Combing the active antenna concept with the reconfigurable antenna technique, a pattern steerable active patch antenna is presented and designed in this paper. A Gunn diode is used to generate the millimeter wave signal and loaded at the centre of the patch antenna. This antenna system has a stable oscillation frequency f : 44.0GHz and operates as a quasi-Yagi patch antenna. The radiation patterns of the antenna can scan in the whole horizontal plane with 3-db beam width by using four reconfigurable states and the radiation main beam of each state directs to the elevation angle 59° in the elevation-plane. The antenna can be applicable to the millimeter wave half-duplex communication and identification systems. 相似文献
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采用2阶皮亚诺分形曲线,设计了一种具有高增益端射特性的微带阵列天线。该阵列天线由多段皮亚诺分形曲线组成,通过添加微带相移器,分形曲线构成了一个偶极子天线阵列。文中介绍和分析了该分形阵列天线的工作原理、结构和主要参数对性能的影响。设计并制作了一只工作于5.8 GHz的分形阵列天线,仿真和测试结果表明,该天线具有良好的辐射特性,其端射增益达19 dB,旁瓣<-12 dB,交叉极化>30 dB,天线口径效率超过90%。 相似文献