一种工作于UHF频段的宽频带互补天线设计

本文应用互补天线的原理,通过采用蝶形平面天线作为电偶极子,采用垂直壁与接地面作为等效磁偶极子,设计了一种新颖的蝶形宽频带天线.该天线实现了62%的相对带宽(1.52-2.89GHz,S11<-10dB),在工作频段内具有稳定的波瓣图,优于-30dB的交叉极化和超过18dB的前后比.     

具有带陷功能的超宽带微带天线设计

UWB天线可以在认知无线电射频前端感知无线频谱,但由于其宽带特性,不可避免地会与传统的窄带无线通信产生相互干扰。为了排除干扰,本文设计了具有带陷功能的UWB微带天线。该天线回波损耗在3.1～10.6GHz范围内满足小于-10dB且驻波比小于2的要求。通过在辐射贴片上挖槽和在接地板上引入缺陷接地结构,最终天线实现了3～4GHz和5～6GHz之间的带陷功能。     

一种新型陷波超宽带天线的设计

文章设计了一种具有陷波特性的超宽带印刷天线,使用高频结构仿真软件HFSS11.0对天线尺寸进行仿真和优化,对天线的阻抗特性、方向图进行了研究.仿真和测试结果表明,该天线在2.3GHz-5GHz和5.9GHz～12.6GHz的工作频段内电压驻波比小于2,且具有稳定的方向图;在5GHz～5.9GHz的阻带范围内具有良好的陷...     

一种小型化五频段可重构蝶形天线的设计

提出了一种新型多频段可重构天线.该天线采用小型平面蝶形结构,尺寸为35.0mm×38.0mm×1.6mm,由U型馈电带线、矩形寄生单元和接地面构成.通过调节馈电带线的长度和选择寄生单元,改变天线的局部结构和表面电流分布,从而获得不同的工作频段.该天线可在1.94～2.22GHz、2.32～2.54GHz、3.08～3.78GHz、3.63～4.83GHz、4.82～6.85GHz五种频段之间实现可重构,覆盖了主要的无线通信系统工作频段,各个状态具有良好的全向辐射特性和较高增益.因此,具有较大的实用价值.     

蝶形双偶极子宽带印刷端射天线设计

文中提出了一款新的蝶形双偶极子宽带印刷端射天线。在该天线设计中,引入阶梯槽线结构来改善天线带宽上的阻抗匹配,拓宽天线的带宽;在地板反射器和双偶极子驱动器上加载蝶形枝节来加长天线的电流流径,实现天线尺寸减小和带宽提高;在不改变天线尺寸的前提下,在引向器上下两边加载寄生贴片,扩大天线辐射口径,进一步提高天线的带宽和增益。所设计的天线被加工成实物并对其进行了测试,结果显示该天线在反射系数低于-10 dB情况下的频率范围为1.59 GHz～3.96 GHz,在相应带宽上,天线的增益为5.84 dBi～8.5 dBi。     

小型化超宽带蝶形印刷对数周期天线

设计了一款用于微波医学成像系统的小型化超宽带蝶形印刷对数周期天线。 在馈电线开端加载电感短柱改善了天线的阻抗匹配,在传统印刷对数周期天线上加载蝶形结构和 U 型贴片结构拓展了天线带宽并实现了小型化。 天线尺寸为 0. 300 λ×0. 280 λ×0. 007 λ( f = 1. 12 GHz) ,天线 S11 <-10 dB 的实测工作频带为 1. 12 GHz ~ 4 GHz,最大实测增益达到6 dBi。 天线的实测方向图在工作频带内实现了定向辐射,辐射效果好,该天线可以应用于微波脑检测系统等医学领域。     

具有陷波特性的超宽带分形缝隙天线

结合超宽带缝隙天线和分形结构的优点,设计了一种具有陷波特性的超宽带分形缝隙天线.选择E形缝隙结构,并在缝隙下边缘采用树状分形,构造半波长谐振结构,实现了天线的陷波功能,有效地避免了超宽带频带范围内的系统干扰.给出了天线设计的总体思路,通过理论分析和仿真测试,对天线的阻抗特性、增益进行了研究.结果表明,该陷波天线的阻抗频带为3 GHz ～12 GHz,在5 GHz～6.25 GHz频带内具有陷波特性.同时,分形结构的引入极大地缩小了天线的尺寸.     

具有双陷波特性的超宽带天线设计与研究

提出一种具有双陷波特性的燕尾形平面超宽带天线.天线的辐射体和地板分别采用椭圆和梯形的渐变结构,具有良好的宽带阻抗匹配特性.通过在辐射体上嵌入两种不同类型的缝隙,使天线具有双陷波功能.计算和实测结果表明,天线在通带(2～3.2GHz、4.3～5.3GHz和6.2～14GHz)频段范围内满足电压驻波比小于2,在3.2～4.3GHz和5.3～6.2GHz两个频段内同时具有陷波特性,并且,天线在通带频段内呈现良好的辐射特性.文末结合天线的实测阻抗曲线给出了一个概念性电路,定性地解释了陷波特性的工作原理.     

基于地板开槽的陷波矩形渐变超宽带天线设计

提出了一种具有陷波特性的UWB天线.该天线用开槽的金属片作为辐射单元,并通过对地板的开槽处理减小了天线的尺寸.结合HFSS仿真工具,对天线结构进行理论优化并通过大量仿真对天线尺寸进行调整;设计出一种基于FR4介质的尺寸为25*15*1mm3的天线模型,并设计模型进行加工测量.该天线的工作频带覆盖3.1～10.6 GHz,并避免了3.5-GHz WiMAX,和5.825-GHz WLAN频段,适于超宽带无线通信系统的应用.     

一种新型具有带阻特性的超宽带天线

提出了一种新型共面波导馈电的,具有带阻特性的平面单极子超宽带天线.为了抑制与WLAN系统的干扰,通过在天线平面上加入调谐支节,从而达到了在WLAN频段上的带阻特性.该天线在回波损耗S11≤-10 dB的工作频带带宽达到了2.49～14.53 GHz,并且在4.9～5.92 GHz频带内形成了阻带.采用基于有限元的电磁场仿真软件HFSS进行了优化,并绘出天线的方向图,结果表明该设计方法的有效性.     

Band-notched ultra-wideband printed open-slot antenna using variable on-ground slits

A novel modified printed ultra-wideband (UWB) slot antenna with a square structure and a trapezoid tuning stub as well as a band-notch characteristic is presented. By embedding two L-shaped slits at the edge of the open radiating slot, a tunable notched band, for avoiding interference between the UWB and WLAN systems, is achieved. Moreover, by optimising the dimensions of the polygon-like slot and tuning stub, the impedance bandwidth and matching of the antenna can be improved. The realised slot antenna operates over 2.6-13.6 GHz for VSWR < 2 and has a rejected band of 4.9-5.85 GHz.     

Dual Band-Notched Small Monopole Antenna with Enhanced Bandwidth for UWB Applications

This article proposes a novel printed monopole antenna for ultra wideband applications with dual band-notch function. The antenna consists of a disc-shaped radiating patch with a pair of folded strips arms, and a ground plane with a two L-shaped conductor backed plane, which provides a wide usable fractional bandwidth of more than 140 % (2.6–14.43 GHz). In order to generate single band-notch characteristics, we use a modified disc-shaped radiating patch with a pair of folded strips arms also by using this modified radiating patch, additional resonance is excited and hence much wider impedance bandwidth can be produced, especially at the higher band. By adding two L-shaped conductor backed plane in the ground plane a dual band notch function is achieved. The measured results reveal that the presented dual band-notch monopole antenna offers a very wide bandwidth with two notched bands, covering all the 5.2/5.8 GHz WLAN, 3.5/5.5 GHz WiMAX and 4 GHz C bands. The designed antenna has a small size of $12\times 18\,\hbox {mm}^{2}$ .     

基于SRR结构的陷波超宽带天线设计

针对超宽带系统易受窄带信号干扰的问题,设计了一种新颖的基于金属开口谐振环(SRR)结构的平面超宽带陷波天线。在天线的辐射贴片上加载U形缝隙,实现了其陷波特性。利用仿真软件研究了U形缝隙的物理尺寸对其陷波特性的影响,并对所设计的超宽带天线进行了制作和测量。结果表明,所制天线在超宽带系统3.1~10.6GHz工作频段的电压驻波比(VSWR)小于2,在WLAN频段具有良好的陷波特性,有效地抑制了超宽带通信系统与窄带通信系统之间潜在的干扰。     

Compact UWB Antenna with High Rejection Triple Band-Notch Characteristics for Wireless Applications

In this paper, small printed flower-shape triple notch ultra-wideband (UWB) monopole antenna with high band rejection is presented. Notch bands include WiMAX (IEEE802.16 3.30–3.80 GHz), WLAN IEEE802.11a/h/j/n (5.15–5.35, 5.25–5.35, 5.47–5.725, 5.725–5.825 GHz), and X-band downlink satellite system (7.1–7.9 GHz). By including inverted T-shape stub and etching two C-shaped slots on the radiating patch, triple band-notch function is obtained with measured high band rejection (VSWR = 14.52 at 3.58 GHz, VSWR = 15.88 at 5.69 GHz and VSWR = 6.95 at 7.61 GHz) and covers a UWB useable fractional bandwidth of 114.30% (2.74–10.57 GHz = 7.83 GHz). In short the antenna offers triple band-notch UWB systems as a compact multifunctional antenna to reduce the number of antennas installed in wireless devices for accessing multiple wireless networks with wide radiation pattern. The proposed antenna has a small size of about 0.25λ × 0.30λ at 4.2 GHz (first resonance frequency), which has a size reduction of 30% with respect to the earlier published antenna. Both the experimental and simulated results of the proposed antenna are presented, indicating that the antenna is a good candidate for various UWB applications.

     

频率可重构超宽带天线研究

超宽带天线和可重构天线是当今天线领域研究的热点。将可重构天线技术应用到超宽带天线设计中,讨论了频率可重构超宽带天线的设计思路。以印刷单极子椭圆天线为原型,给出了两个可重构天线的具体结构,并对天线进行了可重构带阻设计,避免与相关频段之间的干扰。仿真结果表明:重构后天线Ⅱ的低频获得了扩展,其相对尺寸的长和宽分别减小到最大工作波长的0.116倍和0.087倍,工作频段为0.174～10.9GHz,可重构阻带为5.1～5.95GHz,带宽比可高达62:1.     

Electromagnetic band gap coupled tri-notched miniaturized ultra-wideband antenna loaded with slot and parasitic strip

An electromagnetic band gap (EBG) coupled miniaturized tri-notched printed ultra-wideband (UWB) monopole microstrip antenna having dimensions of 22 mm × 26 mm × 1.6 mm loaded with a slot in radiating patch and a parasitic strip in the ground plane has been presented. The proposed structure incorporates a square-shaped metallic radiating patch with a square EBG structure adjacent to the microstrip feed line, a U-shaped meandered slot over the radiating element, and a U-shaped parasitic resonator at the ground plane beneath the radiating element, to reject the C-band satellite downlink (3.7 to 4.2 GHz), WLAN frequency band (5.15 to 5.85 GHz), and X-band satellite downlink (7.25 to 7.75 GHz) frequency bands, respectively. The designed antenna operates in the frequency range from 3 to 11.1 GHz, with an impedance bandwidth of 8.1 GHz and a percentage bandwidth of 114%. Modification steps incorporating into the reference antenna to achieve the desired design objectives have been discussed, along with parametric studies. The proposed design has been simulated using Ansys HFSS, and measurement has been taken using standard measurement technique and compared with the simulated results.     

Genetic algorithm based inversion of neural networks applied to optimised design of UWB planar antennas

An inversion of artificial neural networks using a genetic algorithm is presented for a novel concept of optimisation applied to UWB planar antennas of bow-tie type with respect to specified values of antenna performance in the frequency range 3.1-10.6 GHz. This efficient concept is shown to achieve significant reduction in computing time for optimisation. The multidimensional inversion is characterised by a simple composite fitness or target function that includes antenna parameters as a function of signal frequency or/and angle dependence. Good impedance matching and gain performance is achieved over the whole frequency range by adequately modifying the radiating contour profile of the conventional triangular bow-tie antenna.     

一种共面波导馈电的双陷波渐变槽天线

为了滤除WIMAX(3.3～3.8 GHz)和WLAN(5.125～5.825 GHz)窄带信号对超宽带系统的干扰,该文提出一款共面波导馈电的小型化双陷波渐变槽天线。共面波导结构可以有效地扩展天线的带宽,实现对整个UWB(3.1～10.6 GHz)频段的全覆盖。通过在天线的馈线上开L型缝隙和在辐射贴片上开一对E字型缝隙的方法,有效实现了在3.15～3.97 GHz和4.94～6.05 GHz频段的双陷波特性,能够抑制WIMAX和WLAN对超宽带系统的干扰。该天线结构简单紧凑,尺寸非常小,仅为40 mm×18 mm×0.813 mm。仿真和实测结果表明该天线在超宽带波段内具有良好的陷波特性、增益特性,可以应用于小型化超宽带系统中。文中方法对于陷波渐变槽天线的研究具有一定的借鉴意义。     

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.     

具有双陷波特性的蜂窝结构分形超宽带天线

提出了一款具有双陷波特性的蜂窝结构分形超宽带（ultra-wideband，UWB）天线，采用二阶蜂窝结构作为辐射贴片和缺陷地结构接地板实现良好的超宽带特性.通过在辐射贴片上挖去正六边形和矩形宽缝隙并引入对称鱼钩形枝节，在馈线处刻蚀倒U形窄缝隙产生了3.27~4.27 GHz和7.2~8 GHz两个频段的陷波特性.天线在2.8~11.6 GHz的频段内，可有效抑制WiMAX、C波段卫星和X波段卫星窄带系统的干扰.仿真和实测结果基本吻合，表明该天线适合应用于各种UWB通信系统.