共查询到18条相似文献,搜索用时 93 毫秒
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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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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. 相似文献
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本文设计了一种新型微带馈电的折合平面单极子手机天线,采用时域有限差分法(FDTD)计算并分析了新型折合平面单极子天线几何参数对其性能的影响.实际测试发现,FDTD方法分析所得结果与实验结果基本一致,该天线具有结构简单、宽频带、馈电方便、便于集成等特点,为第三代移动通信手机天线增加了一种新选择. 相似文献
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介绍了一种加载圆锥单极子天线的设计,加载圆锥单极子天线具有形式简单、频带宽、交叉极化低和增益高的优点.通过电磁仿真软件,计算了天线的驻波比和方向图随频率的变化规律.分析表明文中的天线超宽带、全向,满足驻波比的要求,具有良好的应用前景. 相似文献
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A novel multiple meander strip monopole antenna is presented. By iteratively meandering the vertical strip, compactness and broadband characteristics for the monopole antenna were achieved simultaneously. The designed monopole antenna with a radiation element volume of 14/spl times/14/spl times/14 mm/sup 3/ has the measured bandwidth ratio of 3.87:1, from 2.83 to 10.96 GHz for VSWR/spl les/2, with fairly frequency-insensitive omni-directional radiation characteristics. 相似文献
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The radiation and impedance characteristics of a spherically capped conic antenna protruding from a spherical vehicle are studied as a function of cone height, cone angle, and diameter of the vehicle. The conic antenna is excited by a gap at the cone base. The excitation is assumed rotationally symmetric. Considered in detail is the thin conical monopole extending from a sphere. The radiation patterns and antenna impedance referred to the base are calculated and compared with that of a cylindrical monopole over an infinite conducting plane. 相似文献
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Zhi Ning Chen 《Antennas and Propagation, IEEE Transactions on》2005,53(2):672-677
This work presents a bi-arm rolled monopole for ultrawide-band (UWB) applications. The roll monopole is constructed by wrapping a planar monopole. The impedance and radiation characteristics of the proposed roll monopole are experimentally compared with a rectangular planar monopole and strip monopole. Furthermore, the transfer responses of transmit-receive antenna systems comprising two identical monopoles are examined across the UWB band. The characteristics of the monopoles are investigated in both time and frequency domains for UWB single-band and multiple-band schemes. The study shows that the proposed bi-arm rolled monopole is capable of achieving broadband and omnidirectional radiation characteristics within 3.1-10.6 GHz for UWB wireless communications. 相似文献
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为展宽传统单极天线的带宽,通过仿真优化设计,详细研究了一种新颖笼形单极天线的阻抗特性和辐射特性,以及各种参数对天线电性能的影响,最终利用优化结果研制了一种结构紧凑的宽带笼形单极天线。实验证明,该天线具有良好的带宽特性、良好的全向辐射特性、体积小、重量轻等诸多优点,测试结果和仿真结果取得了较好的一致。该天线具有良好的应用前景,可广泛用于机载、弹载、空闻载和地面终端等场合。 相似文献
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设计了一种小型化宽带定向天线。椭圆形的印制单极天线是一种小型化的超宽带天线,通过将该单极天线的地板折叠为字母C的形状,作为单极天线振子的反射腔,不仅实现了天线的定向性,同时进一步减小了天线的高度尺寸(0.13λ0,λ0为工作频率空气波长)。制作了天线样件并进行了测试,实测结果表明,该小型化天线驻波小于3的工作带宽为700~3800MHz,天线的方向图在整个频带内具有良好的定向辐射特性。 相似文献
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The prototype of a compact directional antenna for geophysical diagnostics from a borehole has been constructed and tested. The prototype consists of a wire monopole antenna placed next to a ferrite cylinder which loads the antenna thereby changing its characteristics. At its resonant frequency of 230 MHz, the ferrite-loaded antenna has an input resistance of 19 ?, and is physically shorter by a factor of 2.57 when compared to an unloaded monopole resonant at 230 MHz. The antenna radiation pattern is directional with a front/back ratio of 8.5 dB, and a?3 dB beamwidth of 146° at 249.6 MHz. 相似文献