A New Dual Polarized Aperture—Coupled Printed Array for SAR Applications

This paper presents a new design of dual polarized aperture-coupled printed antenna array,The finite-difference time-do-main(FDTD) analysis of an aperture-coupled microstrip element is performed,and the effects of antenna parameters on ist characteristics are obtained to guide the design of the printed array,Then an 8^2 dual polarized array design in X-band is introduced with configuration plots,In order to improve its isolation and cross polarization.an outphase-displacement feeding technique is adopted in the feed network.Also,the round bends are used instead of conventional right-angle bends so as to acieve better VSWR performance,Experimental results are presented.indicating the validity of the design.This dual polarized array can be applied as a sub-array of paceborne SAR systems.     

具有不同宽槽数的矩形微带贴片天线多带特性研究

主要研究了多带工作的特性,并通过设计矩形贴片微带天线--包含不同数目的并放置在两辐射端的槽, 进行分析. 分析基于MOM仿真软件包, 结论表明一个贴片上有3个槽的天线具有多带特性: 4个振荡频率分别在1. 6, 1. 8, 2. 65, 和4. 83 GHz, 并且具有足够的反射损耗和增益值. 同时证明了带有2对槽的贴片天线(槽分别位于两辐射端)有双带特性, 其振荡频率分别在1. 64和1. 8 GHz, 而且返回损耗和增益值很好.     

Corner-fed microstrip antenna analysis for dual polarization

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用于RFID读卡器的低旁瓣圆极化微带天线阵的设计

A low-sidelobe circularly-polarized （CP） microstrip patch array for 2.4 GHz radio frequency identification （RFID） readers is presented. The antenna array with a Chebyshev current distribution is composed of 6 microstrip elements. The CP operation is obtained by the quasi-square patch with difference in lengths of the two sides. The antenna has been investigated numerically and experimentally. Measured results show that the array has a Chebyshev pattern with the sidelobe level of -23 dB, the half-power beamwidth of 16° and an impedance bandwidth （S11 ≥-10 dB） of 130 MHz, which is suitable for RFID reader applications.     

宽带印刷天线与双极化微带及波导缝隙天线阵(英文)

In order to meet the urgent needs in wireless com-munications , microwave i mage synthetic aperture ra-dars (SAR) ,and electronic warfare systems ,this dis-sertation studies several types of broadband dual-polar-ized planar antenna elements and arrays ,and proposesa few of novel designs with experi mental verification.The main accomplishments reported in the dissertationare as follows . First ,the phenomena of symmetryin electromagne-tism, both in theory and in applications , are sum-marized.…     

宽带印刷天线与双极化微带及波导缝隙天线阵

In order to meet the urgent needs in wireless communications, microwave image synthetic aperture radars （SAR）, and electronic warfare systems, this dissertation studies several types of broadband dual-polarized planar antenna elements and arrays, and proposes a few of novel designs with experimental verification. The main accomplishments reported in the dissertation are as follows.     

Compact wideband microstrip array antenna with beam squint

A compact wideband microstrip array antenna with a squint beam is introduced without the matched load. Its measured beam is at 10° offset to the broadside with a measured gain of 12 dB at 10 GHz. The measured impedance bandwidth (voltage standing wave ratio (VSWR)⩽2) is over 16%, which agrees well with the simulated one. It is a low-cost wideband design with compact simple structure, suited for military and commercial application.     

具有很高隔离度的双极化缝隙耦合微带天线

A wideband dual-polarized slot-coupled stacked microstrip antenna with very high isolation and low cross-polarization is presented. To improve isolation between two poiarization ports, the stacked patches are excited by an open-ended and a T-shaped microstrip lines both via two H-shaped slots placed in a ＂T＂ configuration. The measured isolation is better than 40.5 dB over the bandwidth from 8.8 to 9.8 GHz with cross-polarization level less than - 28.5 dB. The measured VSWR ≤ 2 bandwidths reach 20.7 96 and 19.196 at the verrical and horizontal polarization ports, respectively. This antenna is suitable to be used as array elements in spacebome synthetic aperture radars （SAR） and active phased array radars.     

一种双模圆极化贴片天线设计

为满足卫星导航系统的要求,采用单点馈电叠层贴片技术,设计了一种双频圆极化宽波束天线;采用隐式的时域有限差分方法,对天线进行全波仿真,分析了影响匹配性能的结构参数,并通过在贴片的一组对边上开矩形缝隙,微调天线谐振频率,同时实现了阻抗带宽和轴比带宽相吻合;总结出改善天线双频匹配特性的方法,解决了双频段同时达到最佳匹配的问题。     

双频圆极化卫星定位系统天线设计

为了适应全球卫星定位系统的需要,采用多层重叠的贴片结构,设计了一种双频圆极化天线。其中上层贴片为圆形,下层为矩形,利用开槽技术分别在1．618GHz和2．49GHz频段处实现了圆极化,并且通过在下层贴片的四条边上分别开设矩形槽达到了缩小天线尺寸的目的。同时采用单点同轴馈电,实现了良好的阻抗匹配性能。     

带凹槽的三角形双频微带天线

1　Introduction　Incommunicationsystemapplications ,microstripantennashaveattractedmuchinterestduetotheirlightweightandlowcost.Possibledesignsfordual frequencymicrostripantennasincludedual modedual frequencypatchantennas,multi patchstructuresandreactively loadedpatchantennas,etc[1,5] .Theor thogonal modedual frequencypatchantennasprovidenosimilarradiatingpatternsofthetwooperatingfre quencies .Themulti patchstructureaddstothecom plexityinboththeoreticalanalysisandmanufacturing .Loadingthemicro…     

微带贴片天线的简化全波分析

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ａｎｕｍｂｅｒｏｆｆｕｌｌｗａｖｅａｎａｌｙｓｅｓｈａｖｅｂｅｅｎｐｒｏｐｏｓｅｄｉｎｔｈｅｐａｓｔｔｗｏｄｅｃａｄｅｓ[1～3].Ｔｈｅｓｅａｌｌｐｒｅｄｉｃｔｔｈｅｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｍｉｃｒｏｓｔｒｉｐａｎｔｅｎｎａｓｒｉｇｏｒｏｕｓｌｙａｔｈｉｇｈｅｒｆｒｅｑｕｅｎｃｉｅｓ.Ｔｈｅｓｐｅｃｔｒａｌｄｏｍａｉｎｍｅｔｈｏｄｏｆｍｏｍｅｎｔｓ[3],ｕｓｉｎｇｓｉｍｐｌｅｂａｓｉｓｆｕｎｃｔｉｏｎｓｒｅｑｕｉｒｅｓａｌａｒｇｅｓｉｚｅｍａｔｒｉｘｓｕｃｈａｓ(…     

一种小型三频段印刷天线设计

设计了一种微带线馈电的三频印刷天线,其辐射体有3个尺寸不同的矩形框嵌套而成,调整这些矩形框的长度和位置可以改变独立的电流路径,形成的频段用于WLAN和WiMAX系统。该天线结构简单,尺寸易于调节。测量结果显示:天线10 dB阻抗带宽分别为400 MHz(2.2~2.6 GHz)、700 MHz(3.28~3.98 GHz)和1 310 MHz(5.15~6.46GHz),并且具有良好的辐射特性。     

利用FDTD方法全波分析与设计管道中用于整流天线的微带天线

1 Introduction In some nuclear power plants , chemical plants ,power plants ,the pipe cracks detection is very diffi-cult because of its thinness and fatalness . So the in-pipe inspection micromachine is developed . The rec-tenna (rectifying antenna) ,rec…     

一种圆柱形介质谐振器天线阵列设计

在圆柱形介质谐振器天线单元分析的基础上,设计了一种4单元介质谐振器天线阵列。天线阵采用微带线馈电网络,保证单元之间满足相位匹配关系,使该天线阵列具有良好的定向辐射特性,而且在带宽方面满足要求。     

蝶形微带天线的双频工作

Characteristics of a single-feed dual-frequency bow-tie microstrip antenna are studied. By using the variation method, simple formulas for resonant frequencies of the bow-tie microstrip antenna are derived. It is shown that the dual-frequency ratio can be controlled easily by choosing the parameters of the antenna. This design gives compact antenna size and simple antenna structure. Experimental results are presented, verifying the validity of the design.     

Investigation into effects of buildings near broadcasting antenna on far fields using a finite-difference method

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Novel circularly-polarized ceramic dielectric resonator antenna excited by a corner-cut square patch

A ceramic dielectric resonator antenna excited by a corner-cut square patch for the circularly-polarized operation is introduced. The effect of patch size and cut size is investigated, showing that the resonant frequency of the antenna can be changed by simply changing the patch size. The reflection, axial ratio, and radiation characteristics of the antenna are found. Measurements were carried out to verify the design. The antenna is compact in structure, which is attractive in the application as the satellite communication terminals.     

基于集总参数电路过渡的微带低通滤波器设计

从集总参数滤波器电路设计出发,应用Richards变换方法和Kuroda规则,讨论了由集总参数电路向分布参数电路转化的具体过程,从而完成紧缩结构的微带低通滤波器设计。采用微波仿真软件对所设计的微带电路进行分析,并对设计电路的参数进行了测试。     

多分支平面印刷天线的设计

设计了一种多分支平面印刷天线,采用微带线馈电方式,其中微带线设计成T形,与辐射单元匹配.辐射单元由3个L形的金属面结构构成,其分别工作在2.4 GHz、3.5 GHz和5.4 GHz,可应用于无线局域网（WLAN）和全球微波互联接（WiMAX）系统.通过电磁仿真软件HFSS对这种天线进行设计,在WLAN应用频段上10 dB阻抗带宽分别为1 GHz （4.9～5.9 GHz）和310 MHz （2.24～2.55 GHz）;在WiMAX应用频段上10 dB阻抗带宽380 MHz （3.3～3.68 GHz）.实测结果表明,这种天线具有良好的远场辐射特性,其增益在2.5～4.7 dBi之间.