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%。     

Broadband Stacked Patch Antenna with Low VSWR and Low Cross‐Polarization

A low cross‐polarization broadband stacked patch antenna is proposed. By means of the stacked patch configuration and probe‐fed strip feed technique, the VSWR 1.2:1 bandwidth of the patch antenna is enhanced to 22% from 804 MHz to 1,002 MHz, which outperforms the other available patch antennas (<10%). Furthermore, the antenna has a cross‐polarization level of less than ?20 dB and a gain level of about 9 dBi across the operating bandwidth. Simulation results are compared with the measurements, and a good agreement is observed.     

一种小型化缝隙圆极化印刷天线

设计了一种小型化的方形缝隙圆极化（CP）平面印刷天线,该天线采用在方形缝隙的四个边上均加载尺寸相同的矩形缝隙,使其具有更低的谐振频率;在方形缝隙的任一个加载缝隙里插入与外围地相连的细金属带条以产生微扰,激励出一对相位差90°的差分正交简并模,从而辐射圆极化波。对天线模型进行了优化设计和实物加工,测试结果表明,缝隙加载后天线谐振频率降低了约10%,验证了该小型化措施的有效性;另外该天线在3%的带宽内轴比<3 dB,具有良好的圆极化特性。     

一种新型单馈点宽带圆极化微带天线的设计

介绍了一种新型单层单贴片圆极化微带天线。该天线采用同轴线单点馈电,通过在圆形贴片上开C型缝的方法实现圆极化辐射并同时展宽了天线的阻抗带宽。仿真结果显示,该新型天线工作于C波段时,3dB轴比带宽为2.6%（124 MHz）,VSWR〈2的阻抗带宽达到10%（477 MHz）。证明了在贴片上开C型缝是展宽带宽和实现圆极化的有效方法。     

一种UHF频段小型圆极化微带天线

采用曲流技术在贴片内部开十字形缝隙,在贴片边缘开矩形缝隙,并通过对贴片切角形成微扰,设计了一种UHF频段小型圆极化微带天线。设计的贴片天线尺寸为59×59mm^2（即0．176λ）,与相同频率相同介质的普通微带贴片天线相比有约54％的尺寸下降。天线的实测结果显示,在898—925MHz内回波损耗小于-10dB,在910—920MHz实现圆极化特性。     

一种新型圆极化UHF通用型RFID读写器天线

面向超高频(UHF)通用型射频识别(RFID)读写器天线的应用需求,设计了一款完全覆盖全球UHF(840-960MHz)频段的RFID圆极化读写器天线。天线采用平面缝隙贴片结构,以共面波导(CPW)馈电方式实现宽频带圆极化特性。测试结果表明,天线的阻抗带宽为735-1014MHz(S11<-10dB),相对带宽31.9%,并且在840-960MHz频段内S11<-20dB,3dB轴比带宽为838-1134MHz,相对带宽30.0%,工作频带内有大于3.5dBi的平坦增益。仿真结果与测试结果基本吻合,天线结构精简,易于加工,满足全球UHF RFID读写器天线的应用需求。     

基于UHF频段及微波段分型天线研究

针对工作在UHF频段和微波频段的RFID系统(射频识别系统)要求,设计满足915MHz和2.45GHz多频特性的分型天线,提出采用方形Sierpinski毯结构。针对目前分型天线谐振频率所成的1∶3∶9的特性分析,并对天线部分参数改变,并对二阶毯型贴片天线进行开槽分析研究,提高天线性能,对高频部分降频以达到系统所要求915MHz和2.45GHz的中心频率,达到谐振频率的同时并保证理想的10dB回损带宽。     

应用于北斗和GPS的双频小型圆极化微带天线

介绍了一款能同时应用于北斗卫星导航系统B₃频段(1 268 MHz,±10 MHz)和全球卫星导航系统(GPS)L₁频段(1 575 MHz,±2 MHz)的双频小型圆极化微带天线,并通过叠层技术实现了天线的双频工作性能。采用相对介电常数为9.7的介质材料和表面开槽技术减小了天线尺寸,达到了小型化的要求。通过切角的方法实现了天线的右旋圆极化工作方式。同时,利用基于有限元法的HFSS仿真软件对天线进行了参数仿真和调试。仿真结果表明,在B₃频段天线具有2.2%的阻抗带宽(VSWR<2)和0.5%的3 dB轴比带宽,在L₁频段天线具有3.1%的阻抗带宽(VSWR<2)和0.5%的3 dB轴比带宽。天线仿真结果满足北斗和GPS指标要求,因此具有良好的应用前景。     

WLAN小型双频微带天线的设计与分析

在分析传统缝隙微带天线的基础上,用传输线和空腔模型设计了一种可用于WiFi、WiMAX的WLAN微带天线。在贴片与接地板之间引入短路面使天线实现小型化,在贴片上开U型缝隙产生双频辐射,采用较低介电常数的介质基板和添加空气腔展宽了天线的带宽。仿真结果表明,当电压驻波比VSWR<2.0时,天线在2.45 GHz带宽为200 MHz(2.35～2.55 GHz),增益达到3.8 dB;在5.2 GHz带宽为1 050 MHz(5.0～6.05 GHz)增益达到8.8 dB。该天线覆盖了WLAN的所有频段,整体性能良好,增益较高,结构简单,易于实现,可以为实际无线通信系统的应用提供参考。     

V形微带缝隙天线

提出了一种新颖的V形微带缝隙天线,地板上开一个直角V形缝隙,在V形缝隙的顶角处附加一个小直角三角形补偿隙,通过改变三角形补偿隙面积的大小可以对天线阻抗匹配进行优化,由基片另一侧的箭形微带线终端对缝隙单元馈电。这种天线易于实现宽带特性,设计简单,便于加工。文中给出了天线阻抗和方向图的计算结果,并给出了反射损耗和增益的实验结果。实测结果表明,该天线的阻抗带宽达到了43%,覆盖了1146~1776MHz的频率范围,-10dB阻抗带宽内增益值在4.5~6.5dB之间,平均增益约为5.5dB。     

A VHF Microstrip Antenna With Wide-Bandwidth and Dual-Polarization for Sea Ice Thickness Measurement

A VHF microstrip patch antenna was developed to achieve a bandwidth of 45 MHz (30%) from 127 to 172 MHz with dual-linear-polarization capability. This microstrip antenna, having a size of 117 cm times 117 cm times 27 cm, used low-dielectric-constant foam substrates and dual-stacked patches with capacitive probe feeds to achieve the required wide bandwidth. Four such capacitive feeds were used to achieve dual polarizations with less than -20 dB of cross-polarization level. Twenty-four shorting pins were uniquely used here on the lower patch to achieve 40 dB of isolation between the two polarization ports. This antenna has a measured gain of 8.5 dB at 137 MHz and 10.3 dB at 162 MHz. One advantage observed here at the low frequencies of VHF is that more electrical structures can be easily integrated into the microstrip antenna to improve its performance.     

Wideband CPW-fed slot antenna for DCS, PCS, 3G and Bluetooth bands

A novel CPW-fed wide planar slot antenna with an asymmetrical slot is proposed. The asymmetrical slot is square-like with the same widths but different lengths at the sides. By choosing suitable lengths of this asymmetrical slot, broadband operation can be obtained. From experimental results, the measured impedance bandwidth, defined by 10 dB return loss, can reach an operating bandwidth of 2136 MHz with the centre frequency operating at 2610 MHz for applications to various wireless bands. In addition, the measured radiation patterns within this wide impedance bandwidth have the same polarisation planes and similar radiation characteristics. Each antenna gain within the application bands can be less than 1 dB     

A compact circularly polarized subdivided microstrip patch antenna

A compact circularly polarized subdivided microstrip patch antenna is proposed. The antenna is composed of the interconnection of four corner patches alternating with four strips and a fifth central patch. It presents the very small size of 0.28λ_g by 0.28λ_g at resonance (5.85 GHz), which represents a surface reduction of 60% compared with a conventional microstrip square patch antenna. The proposed antenna exhibits a gain of 4.3 dBi to 5 dBi and an axial ratio lower than 1.8 dB in the range of its bandwidth, which is of 30 MHz     

一种小型化北斗导航终端圆极化天线的设计

设计了一款单馈电的小型圆极化微带天线。在方形贴片上,通过切角和对称开槽的方法,天线获得了良好的右旋圆极化性能,并实现了小型化设计。借助HFSS电磁仿真软件,对天线参数进行了仿真和分析。仿真结果表明,S11＜-10 dB的阻抗带宽为82 MHz,3 dB圆极化轴比带宽为12 MHz,较好地满足了北斗接收天线的设计要求。该设计具有方法简单、易于实现、成本较低等优点,且具有良好的应用前景。     

Adjustable axial ratio of single-layer circularly polarised patch antenna for portable RFID reader

A novel single-layer, proximity-fed technique for a slot-coupled circularly polarised square patch antenna operated in the ultra-high frequency band is presented. In the proposed design a pair of radiating square patches with a cross-slot and a microstrip feed line are both etched on the top of a microwave substrate, and a coupling arrowshaped slot is etched on the bottom of this substrate. Simulated and measured results indicate that the proposed structure can achieve circular polarisation operation. Proper adjustment of the feed coupling gap distance between the patch and the feed line results in good impedance matching and circularly polarised radiation, and an impedance bandwidth (VSWR <= 2) of about 3.74% and a 3 dB axial-ratio bandwidth of about 1.62% were obtained.     

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.     

人体中心网络微带缝隙天线设计和研究

设计了一款小型微带缝隙天线.通过电磁仿真软件CST的参数优化功能,对微带缝隙天线缝隙的长度、宽度、馈电点等参数进行优化,得到了工作频率为2.45GHz,带宽100 MHz、阻抗匹配良好、辐射效率较高的用于人体中心网络的微带缝隙小型天线,根据仿真设计,制作了天线,测试结果和仿真结果吻合较好.     

低雷达截面的超宽带Koch分形槽缝天线

设计了一种具有低雷达截面的超宽带分形槽缝天线。利用"突出角"为90°的Koch分形对方形槽天线进行3次迭代设计后,-10dB阻抗带宽范围由方形槽缝天线的3.0～13.1GHz变为2.8～13.7GHz。仿真和测试结果显示,天线在3GHz和8GHz方向图对称,在整个频段内相对于原天线的增益更稳定,且具有较低的雷达散射截面(RCS)。该天线适用于对超宽带天线具有低RCS要求的场合。     

Slot-coupled microstrip antenna for broadband circular polarisation

A microstrip antenna with broadband circular polarisation (CP) is presented. The proposed microstrip antenna has a circular patch and is excited by a series microstrip-line-feed configuration through the coupling of a ring slot in the ground plane. The broadband operation is achieved by coupling two CP resonant elements, which are due to the circular patch and the ring slot, respectively. A typical prototype using foam material of thickness 5 mm as the antenna substrate is constructed. Measured results show the 3 dB-axial-ratio bandwidth centred at 2500 MHz is more than 10%.     

一种超高频射频识别读写器天线

本文提出了一种适用于我国UHF RFID读写器的宽带圆极化叠层微带天线,通过选用廉价FR4板、空气层介质和对角线切角的正方形贴片组成叠层结构,采用S型水平蜿蜒带条激励主辐射贴片的馈电方式,展宽了天线的阻抗带宽和轴比带宽.所提出的S型水平蜿蜒带条馈电技术,实现了对称的辐射方向性图.给出了天线设计思路,并利用电磁仿真软件分...