一种宽频带方形槽圆极化天线设计

文中提出了一种加载微扰元素的新型宽频带圆极化方形槽天线,它由一个倒L 型微带馈电线、一个L 型枝节、一对矩形槽和一个方形槽地板组成。用这些缝隙槽和枝节作为微扰元素来调节天线表面电流分布,可以激 发出多个圆极化谐振模式,从而实现了宽频带圆极化辐射。为了验证其合理性,加工并测试了天线模型。测量结果 表明,实测小于-10 dB 的阻抗带宽为74. 9%,小于3 dB 的轴比带宽为84. 7%。此外,测量和仿真的峰值增益分别为 4. 88 dBi 和4. 86 dBi。因此,文中设计的圆极化方形槽天线具有宽的圆极化带宽特性。     

一种微带馈电铲形终端椭圆缝隙超宽带天线

设计了一种具有铲形终端微带馈电椭圆缝隙及枝节调节和接地板阶梯凹槽的超宽带(UWB)天线。利用仿真软件HFSS分析了铲形半椭圆、椭圆缝隙及枝节、半圆切槽、接地板与辐射体间隙、接地板三角形切角和阶梯凹槽等结构对天线性能的影响,对天线结构参数进行了优化。实测天线的阻抗带宽为2.8~12.0 GHz,在3.1~10.6GHz范围内基本呈全向性,并且具有较稳定的增益,约为2.5~4.6 d Bi。该天线可广泛用于无线通信领域。     

一种面向无线通信应用的宽频带圆极化天线阵

提出了一种新型宽频带2×2方形缝隙槽圆极化天线阵.天线阵包含一个连续旋转馈电结构、4个非对称U型馈电枝节和一个方形槽接地板.与传统圆极化天线阵所采用的L型馈电枝节不同,首次提出了一种新型非对称U形馈电枝节来改善天线的圆极化性能.利用这些枝节和缝隙槽作为微扰元素,缝隙槽天线阵可以激发多重圆极化谐振模式,进而产生宽频带的圆...     

小型化缝隙加载圆极化及宽带微带贴片天线设计

提出了一种十字形缝隙加载的小型宽带及圆极化微带贴片天线的设计方法。该天线通过在方形贴片上加载一个大尺寸的十字形缝隙实现天线的尺寸缩减,介质基片采用由FR4和空气层组成的层叠结构,在缝隙中嵌入L型枝节,只需通过调整枝节上同轴线馈电点的位置来获得圆极化或宽带阻抗匹配。ANSYS HFSS仿真分析表明,天线的圆极化带宽（AR≤3 dB）为1.7%,阻抗带宽（VSWR≤2）为5.8%,天线在宽带范围内具有稳定的增益,峰值增益为7.8 dB,同时贴片面积缩减了52.3%。改变馈电点的位置可调节两个谐振频率使天线阻抗带宽达到9.4%,比传统的微带贴片天线阻抗带宽提高了114%。     

基于特征模理论的缝隙宽带天线设计

基于特征模理论,设计了一种新型微带缝隙宽带天线.该天线设计中,首先分析了三种不同天线结构的特征模态,得到初步的天线结构;然后依据该结构的特征电流分布,将天线馈源设置在多个模态的特征电流相似区域,激励出所需的目标模式,得到多模谐振,从而提高缝隙天线带宽.天线由一个长矩形缝隙和对称地镶嵌于其两侧的圆形缝隙构成,其馈源设置在...     

基于多模谐振的低剖面宽带贴片天线

为了增加贴片天线的工作带宽和改善其辐射特性,提出了一种基于多模谐振的低剖面贴片天线。通过在矩形贴片的非辐射边加载短路壁降低H面的高交叉极化,在贴片下方加载短路销钉提高TM_1/2,0模式的谐振频率（f_1/2,0）;然后在TM_3/2,0模式的零电流位置处切割一个矩形缝隙来激发辐射缝隙模式（TM_RS）,得到低剖面、宽频带和低交叉极化的三模谐振贴片天线;最后通过增加贴片宽度和调整天线结构,降低TM_1/2,2模式的频率（f _1/2,2）,实现了四模谐振。仿真和实测结果表明该四模谐振贴片天线在0.03λ₀的厚度下可将带宽增加到21.7% (2.67～3.32 GHz).     

带有开口谐振环引向器的新型端射天线设计

设计一种带有开口谐振环(SRRs)引向器的新型端射天线。天线由反射板、地板、辐射单极子和开口谐振环组成。天线的反射板结构使天线在低频处阻抗匹配,有效地提高了天线带宽;用六对开口谐振环结构作为天线的引向器,很好地实现了天线的高增益。仿真和实测结果表明,天线阻抗带宽达到73.7%(2~4.21 GHz),增益为4.3~10.3 dB;在天线的带宽内,天线的辐射方向图稳定,设计的天线满足S波段无线通信领域的需求。     

一种具有陷波特性的多模态频率可重构UWB天线

为了应对在超宽带(Ultra-Wide Band, UWB)系统中频率可重构天线尺寸偏大、模式单一等问题,提出了一种具有陷波特性的多模态频率可重构UWB天线。该天线通过在圆形单极子的辐射贴片上添加T型枝节和刻蚀I型槽、倒U型槽,以获得UWB覆盖范围为2.7～11.6 GHz的宽阻抗带宽,并产生四个陷波带。仿真与实测表明：控制PIN二极管的偏置状态,可以实现单频段、双频段、三频段、四频段和五频段共五种频段下八种工作模式的多模态切换。此天线大小为16 mm×19 mm,较传统单极子天线体积减小了40%以上,实现了小型化。天线的最大增益为4.13 dBi,具有良好的辐射特性。     

超宽带双极化交叉偶极子天线设计

提出一种结构简单的新型超宽带双极化天线。采用交叉偶极子天线实现双线极化;每只偶极子天线由两个八边形环振子构成,同时在八边形环内部加载寄生枝节,引入新谐振点增加天线带宽;天线结构紧凑,尺寸仅为0.3λL?0.3λL(λL为低频截止频率对应的空间自由波长)。对天线进行加工测试,测试结果表明,该天线在1.24~4.42 GHz能够实现电压驻波比(VSWR)<2,相对带宽达到125%,方向图带宽为95%(1.24~3.60 GHz)。天线定向辐射性能良好,在方向图带宽内增益大于7 dB。     

具有双陷波特性的超宽带平面天线设计

设计了一种带有2个陷波频段的超宽带天线。天线的缝隙和馈电枝节采用相反的梯形结构,以实现较好的阻抗匹配。通过在宽缝隙中增加2个线形枝节和1个"E"形结构,使得天线在3.0 GHz~3.9 GHz和5 GHz~6 GHz 2个频段内出现频率阻断。根据天线的阻抗曲线,给出等效谐振电路并对陷波产生的原理进行了分析。最后对天线的远场辐射特性进行分析和阐述,测试结果良好,达到了陷波超宽带天线频率阻断的效果。     

W波段宽带SIW背腔缝隙天线

W波段（75~110 GHz）的电磁波大气吸收率低、波长短、可用频带宽,在雷达、通信等领域应用广泛.文章设计了一种W波段基片集成波导（substrate integrated waveguide,SIW）背腔缝隙天线,-10 dB的阻抗带宽达到28.6%（78.93~105.24 GHz）,覆盖了W波段75%的频带范围.天线采用双层基片结构.上层为SIW谐振腔及四条辐射缝隙构成的谐振辐射单元,谐振腔内同时存在TM₁₃₀与TM₃₁₀混合模、TM₃₂₀模以及TM₃₃₀模三种高次模,和辐射缝隙一起形成多谐特性,实现带宽拓展;底层为通过耦合缝隙馈电的集成波导,易于扩展成平面网络,构建高增益背腔缝隙天线阵列.该天线频带宽、交叉极化低、剖面低、易于与平面微波电路集成、加工成本低,具有良好的应用前景.     

A low profile circularly polarized UWB antenna with integrated GSM band for wireless communication

A novel monopole antenna with wide impedance bandwidth and axial ratio bandwidth (ARBW) is presented. The proposed structure is consisting of a wide slot hexagonal shape with an L-shaped radiator coupled inside the slot. Further, two inverted L-shaped strips are protruded on the opposite corners of the hexagonal patch for better radiation capability. The radiating patch is fed by a semi hexagonal ring feed mechanism followed by a tapered line coplanar waveguide (CPW) for improving antenna performance. The proposed structure is supported by a triangular shaped ground plane. An extremely wide -10 dB impedance bandwidth of around 195% and 3-dB axial ratio bandwidth of 32.5% is achieved. The designed antenna has stable radiation characteristics within the operating band. Proposed antenna is fabricated on FR4 epoxy substrate by means of standard photolithography process and measured results are found in a good match with simulated.     

Triple broadband compact planar inverted F antenna for WLAN and WiMAX

This article proposes a novel antenna structure by slot loading method based on the planar inverted F antenna(PIFA),which is fed by coaxial probe.The antenna structure consists of a new and flexible slot array including five slots.To reveal the mechanism of slot loading in creating new and broad frequency band,the article discusses the performance of the five slots in detail.Simulations with Ansoft HFSS 10.0 indicate that the -10 dB relative impedance bandwidth can reach 17.2 %,8.9 % and 12.1 % that covers ...     

An ultrawideband coplanar waveguide-fed tapered ring slot antenna

In this paper, we present a new coplanar waveguide-fed tapered ring slot antenna for ultrawideband (UWB) applications. This antenna consists of a 50 /spl Omega/ coplanar waveguide feeding line, wideband coplanar waveguide-to-slotline transition, and a pair of curved radiating slots. The impedance bandwidth with VSWR<2 is from 3.1 GHz to more than 12 GHz. The actual operating bandwidth is, however, limited by the distortion of radiation patterns. Such pattern distortion can be attributed to the antenna mode transition and is investigated in this paper with the help of the radiation patterns in the traditional sense as well as a dimensionless normalized antenna transfer function. By suitably allocating such mode-transition phenomenon to the notched band in a UWB radio, we demonstrate that antennas with desirable radiation characteristics in both UWB low and high bands can be readily achieved. The system responses of a transceiving antenna system in free space are addressed as well.     

Coplanar waveguide fed wideband slot antenna

A new design for a coplanar waveguide (CPW) fed slot antenna is presented. The impedance matching and the radiation characteristics of this structure were studied using the method of moment technique. This antenna has an impedance bandwidth (for a VSWR<2) of 49% and a radiation bandwidth of 42% about its 4.8 GHz centre frequency, compared to the 12-20% impedance bandwidth of the standard CPW fed slot antenna. The cross-polarisation in both the principle planes is at least 20 dB below co-polarisation across the entire bandwidth. Simulated and measured results of the antenna are presented. This wideband antenna has significant applications in wireless technologies     

Wideband small patch antenna

A small patch antenna fed by a coaxial probe with a wideband characteristic is presented. By employing dual shorting pins and cutting a slot in the patch, the size of the patch antenna is reduced while its impedance bandwidth is enhanced. The resonant frequency can be reduced by /spl sim/75% when compared with the resonance edge of a conventional patch antenna. The antenna has an impedance bandwidth of 21.5% (SWR<=2) and maximum gain of 2.2 dBi.     

Circularly polarised antenna with switchable polarisation sense

The authors present the design of a wideband circularly polarised antenna with switchable polarisation sense. The basic antenna is a circularly polarised aperture coupled patch antenna with a slot excitation located along the diagonal of a rectangular patch. A second slot is added along the other diagonal and beam-lead pin diodes are inserted in both slots to allow a dual sense operation for a compact structure in a 4% CP bandwidth     

Miniaturized wideband dual linearly and circularly polarized printed square slot antenna for multiradio wireless systems

A dual symmetrical coplanar waveguide (CPW)-fed small size wideband printed square slot antenna (SSA) with dual linearly and circularly polarized radiation capability is presented. The antenna is composed using a square slot, two symmetrical orthogonal CPW feed lines connected to horizontal and vertical arm of L-shaped radiator, an embedded parasitic inverted-L strip at the lower left corner of the square ground slot and engraving slots in the ground plane. Circular polarization (CP) is achieved due to two orthogonal CPW feed lines and a common L-shaped radiator. Isolation between ports is improved by engraving slots at the lower left corner of ground plane and embedded parasitic inverted-L strip. The sense of dual-polarization can be changed in pass-band by changing the port excitation. Measured antenna reveals that an 84.4% (4.6 GHz, 3.15–7.75 GHz) −10 dB impedance bandwidth (IBW) and about 33% (2.03 GHz, 5.12–7.15 GHz) 3-dB axial ratio bandwidth (ARBW). Isolation between ports <−16 dB is achieved over usable CP band.     

一种小型化超宽带MIMO天线设计

提出了一种基于槽天线的小型化、高隔离度的超宽带(Ultra Wideband, UWB)多入多出(Multiple-Input Multiple-Output, MIMO)天线.该MIMO天线由两个槽天线单元构成, 为了增加天线阻抗带宽, 每个槽天线单元由末端带有圆形贴片的微带线和末端为圆形的槽线两部分耦合馈电.采用在地板上开槽和方向图分集方法, 减少地板表面波和空中电磁波影响, 达到提高天线隔离度的目的.数值仿真和实验结果表明:该天线在3.1~11 GHz频段内满足端口反射系数|S₁₁| < -10 dB, 隔离度|S₁₂|在7~11 GHz频段内小于-25 dB, 在3.1~7 GHz频段内小于-16 dB, 并根据仿真和测试S参数计算了包络相关系数.