梯形接地板结构超宽带天线设计

在圆形单极天线的基础上进行改进设计了一款梯形接地板结构的超宽带单极天线。根据接地板电流的分布强弱,削去矩形接地板两端对电流影响较小的三角形形状部分,构成梯形接地板。经过仿真优化实验结果表明,该天线电压驻波比VSWR2的阻抗带宽为3.1~17 GHz,工作频段内具有全向辐射特性,且天线只有20 mm×22 mm×1.6 mm,结构简单,适合超宽带无线通信系统的要求。     

一种具有三阻带和高频截止特性的超宽带天线

为了有效抑制超宽带(UWB)通信系统和窄带通信系统之间潜在的干扰,设计了一款具有三阻带特性和高频截止特性的超宽带天线。天线总尺寸为33 mm×19 mm×1 mm。该天线的辐射单元由一个椭圆形的单极子和一个倒梯形结构组成,由50的矩形微带线馈电,接地板由一个矩形和一个开槽梯形结构构成。对天线进行加工并测试。结果表明,该天线在3.3~3.6 GHz处的阻带由辐射单元上的凹形槽产生,5.15~5.35 GHz和5.725~5.825 GHz处的阻带由微带馈线两旁的U形寄生单元产生,10.8 GHz高频处的截止特性是由微带线两旁对称的凹形寄生单元共同决定的。天线的测试结果与仿真结果吻合良好。     

一种具有三阻带和高频截止特性的超宽带天线

为了有效抑制超宽带(UWB)通信系统和窄带通信系统之间潜在的干扰,设计了一款具有三阻带特性和高频截止特性的超宽带天线。天线总尺寸为33 mm×19 mm×1 mm。该天线的辐射单元由一个椭圆形的单极子和一个倒梯形结构组成,由50的矩形微带线馈电,接地板由一个矩形和一个开槽梯形结构构成。对天线进行加工并测试。结果表明,该天线在3.3~3.6 GHz处的阻带由辐射单元上的凹形槽产生,5.15~5.35 GHz和5.725~5.825 GHz处的阻带由微带馈线两旁的U形寄生单元产生,10.8 GHz高频处的截止特性是由微带线两旁对称的凹形寄生单元共同决定的。天线的测试结果与仿真结果吻合良好。     

具有陷波特性梯形印制单极超宽带天线

设计了带三角形槽梯形辐射元和阶梯接地面的30 mm×30 mm印制单极超宽带天线原型.实验结果表明,原型天线驻波比小于2的阻抗带宽为2.8 GHz～12.81 GHz,频带内天线具有全向辐射特性,增益变化平坦,相位中心稳定.通过对原型天线振子体的缝隙加载,实现了具有带阻特性的陷波超宽带天线,其驻波比大于3的陷波频带为4.8 GHz～6.0 GHz,陷波频带内最高增益抑制为9 dB,而其他频段性能与原型天线基本一致.     

一种新型超宽带“花型”通信天线的设计和研究

文章设计了一种新型的超宽带“花型”通信天线,其阻抗带宽在2.5GHz到23GHz内的驻波均小于2,相对带宽为160.8%,该天线具有尺寸小、剖面低、重量轻、结构简单的特点,可直接由50Ω微带传输线馈电.利用电磁仿真软件CST对天线进行了仿真和优化,仿真结果和实测结果吻合很好,证明了文章提出的“花型”通信天线具有超级宽带特性     

一种新颖小型共面波导馈电的超宽带天线设计

设计了一种新颖小型共面波导馈电的喇叭形超宽带天线,接地面不同于传统矩形而采用接地面围绕辐射体两侧向顶部延伸的方式,并且靠近馈线的接地面使用两阶阶梯凹槽,利用仿真软件仿真优化辐射体和接地面的结构参数,天线加工后的尺寸为27 mm×30 mm×1.6 mm,实测阻抗带宽为2.5～12.0 GHz,在3.1～10.6 GHz范围内基本呈全向性,并且具有较稳定的增益,约为2.5 ～ 6.0 dBi.     

利用短路片结构的小型超宽带单极天线

介绍了一种利用短路片结构的小型超宽带(UWB)平面单极天线,采用椭圆型金属片作为辐射单元,用同轴线进行馈电.通过将辐射单元和接地板用短路片相连,降低了阻抗带宽低频端的频率,扩展了带宽,并缩小了天线的尺寸.仿真和实测结果表明,该天线的阻抗带宽覆盖了3.1～10.6GHz的民用超宽带频段.     

一种新型超宽带平面单极天线的设计

提出了一种新型超宽带平面单极子天线。该天线由一个倒置的月牙形金属贴片和一个槽口金属接地板构成,采用微带线对其进行馈电。通过数值仿真和实验测量,该平面结构的单极天线具有超宽带性能,实测天线的-10dB回波损耗的频率覆盖范围为3．2～1．8GHz,相对带宽达115％,阻抗带宽达到3．6倍频。且该天线体积小、结构简单、加工简便,适合应用于短程超宽带通信系统。     

新式凹槽形缝隙超宽带微带天线的设计

针对窄带微带缝隙天线带宽较窄的问题,设计了一种新式凹槽形缝隙超宽带（UWB）微带天线。利用微带馈电线激励凹槽形缝隙的方式实现天线带宽的展宽,并得到了良好的效果。经过高频电磁仿真软件HFSS的设计仿真结果表明,该缝隙天线具有良好的阻抗匹配特性,其阻抗带宽（S11<–10 dB）为117% （2.2 GHz～8.4 GHz）,符合超宽带天线的标准。经过测试其阻抗带宽为113% （2.2 GHz～8 GHz）,且最高增益可达6 dB,平均增益为4 dB,具有小型化、集成度高、制作简单的优点,可用在多种通信系统中,应用前景良好。     

一种新型平面超宽带天线的设计

提出了一种微带线馈电的新型平面超宽带单极天线。该天线由带有弧边的金属贴片与开槽接地板构成,通过等腰梯形与圆弧形相结合的方式对接地板进行开槽,将其等分为相互耦合的两部分,起到了阻抗匹配与拓宽带宽的效果。仿真结果表明反射损耗在-10 dB以下的频率覆盖范围为3～11.8 GHz,并且在3.4～11.2 GHz频带驻波比在1.5以下,具有良好的全向辐射特性。该天线结构简单,体积小,适合在UWB通信中应用。     

A novel broadband circularly polarised monopole antenna

A novel broadband circularly polarised (CP) monopole antenna is designed and implemented in this article. The antenna consists of a radiating patch that is composed of an annular-ring linked by a square ring over the corner and a modified ground plane. The broadband property is achieved based on a novel monopole structure that is connected by two perturbed loops, so the CP wave is generated due to the perturbation. Besides, by cutting a rectangular slit and embedding a vertical stub on the ground plane, the impedance and axial-ratio (AR) bandwidths can be greatly enhanced. The measured results reveal that the proposed monopole antenna has an impedance bandwidth of 4.575 GHz from 2.3 to 6.85 GHz, reaching the particularly broad bandwidth of 99.5%. Furthermore, a wide 3-dB AR bandwidth of 34.6% (1.53 GHz, 3.65–5.18 GHz) centred at 4.42 GHz is achieved. The radiation characteristics of the designed antenna are also presented.     

Multi band multi polarized reconfigurable circularly polarized monopole antenna with simple biasing network

Design of a reconfigurable multiband multi polarized monopole antenna with simple bias circuit is presented. The proposed antenna consists of simple radiating truncated rectangular patch with a cross-shaped slit and a ground plane embedded with L-shaped slit. The antenna produces two separate impedance bandwidth with three senses of polarization namely right hand circular polarization, left hand circular polarization and linear polarization. PIN diode is used to reconfigure the L-shape slit in the ground plane. The antenna generates dual band behavior with multiple circularly and linearly polarized bands. With OFF state of the diode, the impedance bandwidth of the antenna is 10.22% and 83.43% from 3.99 GHz to 4.42 GHz and 5.84 GHz to 14.20 GHz, respectively, while 3-dB axial ratio bandwidths are 9.83% and 13.73% from 5.79 GHz to 6.39 GHz and 8.49 GHz to 9.74 GHz, respectively. In the ON state, antenna also shows the dual band behavior with an impedance bandwidth of 49.10% and 21.31% from 7.20 GHz to 11.04 GHz and 12.66 GHz to 15.37 GHz, respectively, while 3-dB axial ratio bandwidth of 6.49%, 8.45% and 2.0% from 7.90 GHz to 8.43 GHz, 10.08 GHz to 10.97 GHz and 12.87 GHz to 13.13 GHz, respectively.     

A Wideband Cross Monopole Antenna

Configurations of planar cross monopole antennas have been investigated. The cross-shaped patch comprises vertical microstrip and two rectangular patches (area A). Effect of rectangular patches (A) of planar cross monopole antennas on the bandwidth has been studied. Another dielectric substrate (075BCT) is used in order to optimize the size. Those antennas provide wideband characteristic and nearly omni-directional radiation pattern. Simulations and experiments demonstrate that this structure exhibits a wide impedance bandwidth, which is over 70% for ${rm S}_{11}leq 10 {rm dB}$ ranging from 2.18–4.78 GHz, which is enough to cover DECT/IMT-2000/3G/UMTS/2.45-GHz ISM band (WLAN, IEEE 802.11b and g)/Bluetooth/ZigBee 2.4 GHz/2.5-GHz WiMAX/3.5-GHz WiMAX bands.      

Dual-band CPW-fed Y-shaped monopole antenna for PCS/WLAN application

A rectangular notch is introduced to expand the impedance bandwidth of a dual-band planar monopole antenna for application in PCS/WLAN systems. The antenna is fed by a CPW line and resembles the shape of the letter 'Y'. Prototypes of the proposed antenna have been constructed and tested. Good measured radiation characteristics of monopole-like patterns, 14.4 and 34.1% bandwidths, and 3 and 4.3 dBi peak antenna gains for the lower (1.95 GHz) and upper (5.45 GHz) bands have been obtained.     

Small broadband disc-loaded monopole antenna with probe feed and folded stripline

A small broadband disc-loaded monopole antenna with a probe feed and folded stripline is presented. The antenna is composed of a rectangular disc with multiple shorting pins and a probe feed with a folded stripline that are coupled electromagnetically. The dimensions of the proposed antenna are 12/spl times/12/spl times/10 mm, and it has a measured impedance bandwidth of 700 MHz for VSWR <2 with a centre frequency at 2.54 GHz, which is approximately 27.5% of a fractional bandwidth.     

Compact microstrip-line-fed ring monopole antenna with tuning strip for 5 GHz WLAN operation

A novel compact and simple microstrip monopole antenna for 5 GHz wireless local area network (WLAN) operation is proposed. To excite a resonant mode in the operating band, a tuning strip is added to the antenna, which consists of a rectangular ring microstrip and a top loaded vertical strip, and is fed by a 50 /spl Omega/ microstrip line. The effects of the added strip to the impedance matching have been studied. A constructed prototype of the proposed antenna has been tested and bandwidth of about 930 MHz ranging from 5.03 to 5.96 GHz, monopole-like radiation pattern, and average gain of greater than 2.6 dBi over the operating band have been obtained.     

Ultrawide-band square planar metal-plate monopole antenna with a trident-shaped feeding strip

A square planar metal-plate monopole antenna fed by using a novel trident-shaped feeding strip is presented. With the use of the proposed feeding strip, the square planar monopole antenna studied shows a very wide impedance bandwidth of about 10 GHz (about 1.4-11.4 GHz, bandwidth ratio about 1:8.3), which is larger than three times the bandwidth obtained using a simple feeding strip (about 1.5-3.3 GHz, bandwidth ratio about 1:2.3). In addition, the proposed feeding strip can be integrated with the square planar monopole, that is, the feeding strip and the square planar monopole together can be easily fabricated using a single metal plate, making the proposed antenna easy to construct at a low cost. Details of the experimental and simulation results for the proposed planar monopole antenna are presented and analyzed.     

基于开窗结构和寄生单元的双陷波超宽带天线

设计了一种具有双陷波特性的平面超宽带天线。超宽带基础天线的馈电采用渐变式阶梯阻抗匹配结构作,使得天线具有了宽阻抗匹配能力。通过在椭形辐射器内进行开窗,以及在地面添加矩形寄生单元,实现了天线的双陷波特性。测试结果表明,该天线的工作带宽(VSWR<2）为3.1~10 GHz,工作在超宽带(UWB)频率范围,两个陷波分别在3.3~4.0 GHz和5.0~5.85 GHz,可以应用于WiMAX和WLAN频段的信号抑制。仿真与实测结果表明,该天线结构简单、实现了良好的陷波功能,能够较好地应用于超宽带通信系统中。     

Triangular quad-port multi-polarized UWB MIMO antenna with enhanced isolation using neutralization ring

In this study, a quad-port multi-polarized ultra-wideband (UWB) multiple input multiple output (MIMO) antenna system with a new isolation technique is designed for wireless devices. The antenna structure consists of four triangular monopole elements and neutralization ring (NR) structures. The monopoles are back-to-back positioned in symmetrical and orthogonal arrangement. Therefore, they radiate towards four directions without interference, and thus the diversity performance is improved. A novel NR is formed by combining a rectangular ring and a straight line to reduce the mutual coupling due to interoperation of the elements. Each triangular monopole is fed by 50 Ohm microstrip transmission line (MTL) with a thin strip line for ensuring impedance matching. Antenna performance in terms of impedance bandwidth, current distribution, radiation pattern, peak gain and envelope correlation coefficient (ECC) is also investigated. The MIMO antenna system has 3.1–17.3 GHz impedance bandwidth, 1–5 dBi peak gain variation, less than 0.1 ECC. The results indicate that the proposed antenna has the characteristics of larger UWB bandwidth, high isolation by the NR structure, multi-polarization, uniform gain and quasi-omnidirectional pattern.