一种新型低剖面宽带微带开槽天线的设计

针对低剖面微带天线,提出一种新型的带宽展宽方法。通过在低剖面E-形微带天线中引入分布式LC谐振电路,使得该分布式LC电路产生的谐振点与低剖面E-形微带天线的固有谐振点相互靠近,从而有效地拓宽了天线的带宽。基于该设计思想,设计出工作于AMPS频段(824～894MHz)的低剖面微带天线,该天线的空气层厚度仅为0.0344λ0,远小于国内外文献报道的同类天线。测量结果表明:设计出的低剖面微带天线工作带宽达到9%(VSWR2),而且在该阻抗带宽内具有良好的辐射特性。该设计思想同样适用于其他形式的低剖面开槽微带天线设计。     

一种新型小型化微带天线的分析与设计

针对传统微带天线低频端尺寸较大的缺点,设计了一种新型微带天线结构,即通过采用在传统微带天线贴片下方挖出凹槽,将辐射板放入凹槽中的办法,设计了一副小型化微带天线。与普通微带天线相比,新型天线谐振频率降低了870MHz,阻抗带宽从原来的170MHz增至560MHz,且天线在整个工作频段内具有良好辐射特性,从而验证了该设计方案的正确性。     

一种新型U型槽宽频微带天线

提出一种新型的低剖面宽带开槽微带天线。该天线通过U型槽加载,从而产生新的谐振点,达到展宽带的目的。采用HFSS软件对提出的天线模型进行仿真优化,结果显示,该天线在12.83 GHz、15.06 GHz两个频点产生谐振,天线阻抗带宽达到940 MHz和770 MHz     

X波段宽带圆极化微带天线的设计

介绍一种新型宽带圆极化微带天线。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,实现了圆极化并辰宽了阻抗带宽;采用层叠结构,使上下两层贴片谐振于相近的频率,从而显著提高了天线的轴比带宽和阻抗带宽。仿真结果显示,该新型天线工作于X波段时,3dB轴比带宽为13．9％,VSWR〈2的阻抗带宽达到35．4％。结果证明,在贴片上开C型缝是实现圆极化的有效方法。     

单馈点宽带圆极化微带天线设计

设计了一种单点馈电的宽带圆极化微带天线。针对微带天线带宽窄的问题,采用双层矩形贴片的层叠结构,通过辐射贴片之间的谐振耦合使天线的频带展宽,得到了良好的效果。在保证天线增益性能的基础上,增加了天线圆极化带宽。采用商用仿真软件HFSS对天线结构尺寸进行了优化设计,仿真结果显示,该天线工作于L波段时,VSWR<2的阻抗带宽达到10%,轴比特性良好,且在整个带宽范围内,天线增益和辐射方向图保持良好的一致性。     

类Sierpinski分形天线的分析与设计

提出了一款应用于L波段的类Sierpinski分形圆极化微带天线。该天线采用类Sierpinski分形结构和π型枝节技术,延长表面辐射电流路径,降低天线的谐振频率,实现天线小型化。天线工作在1.48 GHz的中心频率下,具有良好的圆极化性能。通过仿真分析与模型优化,天线最终尺寸为56 mm×56 mm×1.6 mm,工作频率为1.46～1.50 GHz,天线的-10 dB阻抗相对带宽为2.7%,3 dB轴比相对带宽可达0.4%,最大增益可达1.9 dB。     

UWB天线的宽带化技术及其发展

在现代通信技术中,为了实现通信保密、排除干扰、提高通信效率等,超宽带系统得到了大力发展,然而,在一定程度上却受制于系统中超宽带天线的阻抗带宽。详细介绍了展宽天线阻抗带宽的4种方法,包括渐变阻抗方法、分形几何方法、微带天线开槽方法和非频变结构方法,其中分形几何方法由于其几何结构的自相似性使得其贴片电流分布具有自相似性,从而导致天线的多频点谐振,有效拓展了天线带宽。上述4种天线尽管作用原理互不相同,但在超宽带天线的工程应用中,研究者可将这些方法单独或同时应用于天线结构设计,使得天线既能保持良好的方向性和增益等性能,又能获得较大带宽。     

具有CSRR缺陷地RFID天线小型化设计研究

设计出一款可应用于射频识别(RFID)系统的5.8GHz传统微带矩形贴片天线。天线的辐射贴片尺寸为15.5mm×11.5mm,-10dB的阻抗带宽为80 MHz,最小回波损耗为-36.138dB。在传统微带天线的基础上,设计出一款采用互补开口谐振环(CSRR)缺陷地结构进行改进的小型化天线,天线的辐射贴片尺寸为10mm×7.5mm,-10dB阻抗带宽为62 MHz,最小回波损耗为-23.574dB。相比传统微带天线,改进后的天线的辐射贴片尺寸减小了57.9%,小型化的效果明显且带宽特性和增益特性都能符合RFID系统的一般要求。     

具有CSRR缺陷地RFID天线小型化设计研究

设计出一款可应用于射频识别（RFID）系统的5.8 GHz传统微带矩形贴片天线。天线的辐射贴片尺寸为15.5 mm×11.5 mm,-10 dB的阻抗带宽为80 MHz,最小回波损耗为-36.138 dB。在传统微带天线的基础上,设计出一款采用互补开口谐振环（CSRR）缺陷地结构进行改进的小型化天线,天线的辐射贴片尺寸为10 mm×7.5 mm,-10 dB阻抗带宽为62 MHz,最小回波损耗为-23.574 dB。相比传统微带天线,改进后的天线的辐射贴片尺寸减小了57.9%,小型化的效果明显且带宽特性和增益特性都能符合RFID系统的一般要求。     

几种共面波导耦合馈电装置的特性研究

该文研究了4种共面波导耦合缝对单贴片微带天线的谐振频率以及带宽的影响,并利用天线近场分布对其进行解释;分析并比较了几种耦合缝的馈电特性,极大地提高了天线设计的灵活性;运用变频思想对馈电装置进行改进设计出了一阻抗带宽达28.9%的宽频带天线,在3.76～4.80GHz的工作频段内天线增益均大于8dBi,增益带宽达24.2%。     

Design and Analysis of Triple-Band Rectangular Microstrip Antenna Loaded with Notches and Slots for Wireless Applications

In this paper, a rectangular triple-band microstrip antenna has been designed for Bluetooth application by successively loading notches and slots of different dimension in radiating patch. The conventional microstrip antenna suffers with narrow impedance bandwidth. The current work affords an alternate option to enhance the bandwidth of antenna that resonates in triple-band operation. Initially, the antenna is resonating in single-band but after loading slots, the bandwidth of microstrip antenna has been obtained 1.97% (lower band), 10.35% (middle band) and 33.16% (upper band) resonating in triple-band with three resonant frequency at 1.422 GHz (lower resonant frequency), 1.791 GHz (middle resonant frequency) and 2.467 GHz (higher resonant frequency). The suggested antenna has upper frequency band in the range of 2.045–2.858 GHz resonating at 2.467 GHz frequency and it is appropriate for Bluetooth applications (2.40–2.48 GHz) and both lower band useful for other wireless (L-band) applications. The return loss of upper band is ??34.52 dB at 2.467 GHz. The suggested microstrip antenna is directly fed by 50 ohm microstrip line feed. The suggested antenna has been designed, simulated and analyzed by IE3D simulation software.

     

一种用于微带半波振子天线的新型BALUN

通过将常规的空气板线BALUN微带化，从而建立一种新型微带BALUN。该BALUN引入一个并联谐振电路，可以有效补偿半波振子的串联电抗而实现微带半波振子带宽的最大化。采用此种BALUN设计制作了一个L波段微带偶极子天线单元。测试结果表明：该半波振子天线在21．8％的带宽内驻波比优于1．18，带内交叉极化优于一21dB，接近理论最大设计带宽。     

A New Compact Microstrip-Fed Dual-Band Coplanar Antenna for WLAN Applications

A novel compact microstrip fed dual-band coplanar antenna for wireless local area network is presented. The antenna comprises of a rectangular center strip and two lateral strips printed on a dielectric substrate and excited using a 50 Omega microstrip transmission line. The antenna generates two separate resonant modes to cover 2.4/5.2/5.8 GHz WLAN bands. Lower resonant mode of the antenna has an impedance bandwidth (2:1 VSWR) of 330 MHz (2190-2520 MHz), which easily covers the required bandwidth of the 2.4 GHz WLAN, and the upper resonant mode has a bandwidth of 1.23 GHz (4849-6070 MHz), covering 5.2/5.8 GHz WLAN bands. The proposed antenna occupy an area of 217 mm² when printed on FR4 substrate (epsiv_r=4.7). A rigorous experimental study has been conducted to confirm the characteristics of the antenna. Design equations for the proposed antenna are also developed     

Performance enhancement of rectangular microstrip patch antenna using double H shaped metamaterial

In this paper a high performance rectangular microstrip patch antenna (RMPA) has been designed using doubleHshaped metamaterial. First, the doubleHshaped metamaterial has been designed and optimized at 5.2 GHz resonant frequency of patch antenna. It has been found that embedding of this metamaterial into the substrate beneath the reference patch antenna improves its return loss and bandwidth without changing the resonant frequency and gain. To further enhance the gain and efficiency of the metamaterial embedded RMPA a superstrate of double H shaped metamaterial has been applied at the distance of -/3 over it. Finally, a high gain, broadband and good impedance matched metamaterial inspired RMPA has been obtained. The proposed antenna was simulated and optimized using HFSS software. The prototype antenna has been fabricated and measured results of the proposed antenna are found to be in good agreement with the simulated results.     

双频宽带大型微带反射阵天线设计

微带反射阵天线在性能上最主要的缺陷就是窄带,一般情况下其带宽小于5%,对电大口径短焦距馈电时更窄。本文设计并制作出一种由L波段和C波段两个反射面天线组成的6m×2m薄膜双频微带反射阵天线,两个频段的天线共用一层膜面。对该天线的电性能进行了测试,测试结果表明:该天线两个频段的相对带宽均大于10%(副瓣电平≤-18dB)。该天线具有折叠、可展开的结构特征,可以在卫星或航天器上广泛应用。     

一种小型化宽带圆极化微带天线的设计

设计并加工了一种采用同轴背馈方式馈电的小型化宽带圆极化微带天线。针对单点馈电微带天线轴比带宽窄的问题,通过增加馈电网络对天线辐射贴片进行双点馈电以展宽轴比带宽,得到了良好的效果。馈电网络根据带状线理论设计,利用U形接地板巧妙地实现了宽带天线的结构小型化。通过对辐射贴片的双点馈电获得了令人满意的电压驻波比带宽和良好的圆极化性能。通过仿真和实际测试表明,该天线VSWR≤2的带宽达到了30％,3dB圆极化带宽约为26％,同时频带内天线的增益达到4dB。     

宽带E型贴片天线的设计

本文在矩形微带贴片天线的基础上,通过在贴片上开两条对称的缝隙而得到E型贴片天线.经过仿真优化计算出E型贴片天线的尺寸,确定了最终方案模型,得到了方向图、回波损耗等参数.设计的天线工作频率为1.88GHz到2.4GHz,带宽达25.2％,谐振频率的增益达9.38dB.该天线拥有结构简单、体积小、宽频带特点,具有很好的实际...     

Broadband dual frequency microstrip antenna

A new dual port microstrip antenna geometry for dual frequency operation is presented. The structure consists of the intersection of two circles of the same radius with their centres displaced by a small fraction of the wavelength. This antenna provides wide impedance bandwidth and excellent isolation between its ports. The gain of the antenna is comparable to that of a standard circular microstrip antenna operating at the same resonant frequency. A theoretical analysis for calculating the resonant frequencies of the two ports is also presented     

A modified contour Integral analysis for Sierpinski fractal carpet antennas with and without electromagnetic band gap ground plane

A modified contour integral method coupled with segmentation method has been used, for the first time, to analyze both the Sierpinski fractal carpet (SFC) antennas of different orders and an SFC antenna with electromagnetic band gap (EBG) ground plane. The close agreement between the calculated and measured results for resonant frequencies and input return losses indicates that this technique can be used to accurately predict the impedance characteristic. A novel stacked microstrip Sierpinski carpet fractal antenna using the EBG ground plane is also presented. Comparing to an ordinary microstrip fractal antenna, which has a maximum bandwidth of approximately 2%, the proposed antenna has a higher input impedance bandwidth of nearly 9%. The radiation patterns of the proposed antenna are improved due to the removal of unwanted radiation caused by the surface wave. The experimental measurement results of the proposed antenna are presented in this paper.