两层改性环形谐振器覆盖的分形PeaNe天线(IJWMT-V5-N2-1)
阶跃阻抗谐振器结构的双频差分天线
阶跃阻抗谐振器结构的双频差分天线
马润波;张文梅
【期刊名称】《测试技术学报》
【年(卷),期】2011(025)005
【摘要】提出了一种采用阶跃阻抗谐振器(SIR)结构设计的同轴馈电双频差分天线.天线具有对称结构,其传输线模型包含两个谐振单元.通过对谐振单元的简化和分析,证明了谐振单元类似于标准的1/4波长SIR,并导出了谐振单元的电长度和阻抗比与双频天线工作频率的关系.依照该方法设计了一个2.4/5.2 GHz的双频差分天线,同时用模型仿真的方法优化了天线的馈电位置.所实现的天线尺寸为28.2mm× 23.5 mm,相当于0.4λ×0.33λ.通过制作和实测,天线工作在2.38 GHz和5.11 GHz,对应的增益分别为1.9 dBi和6.6 dBi.仿真和测试结果表明,采用阶跃阻抗谐振器设计双频差分天线的方法是可行且有效的.
【总页数】7页(P414-420)
【作者】马润波;张文梅
【作者单位】山西大学物理电子工程学院,山西太原030006;山西大学物理电子工程学院,山西太原030006
【正文语种】中文
【中图分类】TN823+.24
【相关文献】
1.基于阶跃阻抗谐振器的新型双频宽带带通滤波器 [J], 胡金萍;李国辉;景冻冻;吴辉;马艳忠
2.采用折叠型阶跃阻抗谐振器的新颖双频带带通滤波器 [J], 马德臣;肖中银;相亮亮;黄春艳;寇鑫;吴效环
3.采用阶跃阻抗谐振器的小型化双频天线 [J], 马润波;张文梅
4.基于阶跃阻抗谐振器的RFID无芯片标签 [J], 孙海静;陈强;杨娇;周玲;朱俊涛
5.基于阶跃阻抗谐振器的RFID无芯片标签 [J], 孙海静;陈强;杨娇;周玲;朱俊涛
因版权原因,仅展示原文概要,查看原文内容请购买。
一种应用于WLAN双频的T型介质谐振器天线
一种应用于WLAN双频的T型介质谐振器天线郑浩天;林文斌;阚国锦;邹德友【期刊名称】《现代电子技术》【年(卷),期】2017(040)021【摘要】A T-type dielectric resonator antenna meeting the requirement of WLAN dual-band was designed. Two sides of the dielectric resonator are cut to form the T-type antenna to produce dual-band radiation. The electromagnetic simulation soft-ware is used to establish and optimize the model to get the best design parameters of the antenna. The simulation result shows that the antenna can work at 5.8 GHz and 5.2 GHz,and has a high gain. The antenna has simple structure. The T-type processing for dielectric resonator is only performed on the basis of traditional rectangular dielectric resonator antenna.%设计一种满足WLAN双频的T型介质谐振器天线.通过对介质谐振器两侧进行切割形成"T"型产生双频辐射,再由电磁仿真软件建立模型并对其优化,得到最佳的天线设计参数.仿真结果表明该天线实现了5.2 GHz和5.8 GHz的双频带工作且均有很高的增益.该天线结构简单,仅在传统矩形介质谐振器天线的基础上对介质谐振器进行了"T"型处理.【总页数】3页(P46-48)【作者】郑浩天;林文斌;阚国锦;邹德友【作者单位】西南交通大学电磁场与微波技术研究所,四川成都 610031;西南交通大学电磁场与微波技术研究所,四川成都 610031;西南交通大学电磁场与微波技术研究所,四川成都 610031;西南交通大学电磁场与微波技术研究所,四川成都610031【正文语种】中文【中图分类】TN82-34【相关文献】1.一种应用于WLAN的双频微带天线的设计 [J], 丁晓倩2.一种应用于WLAN的定向辐射紧凑型双频PIFA天线设计 [J], 徐圣彬3.一种应用于GPS和WLAN的高增益双频天线的设计 [J], 吴家国;周晓明4.一种应用于WLAN的双频段平面单极子手机天线 [J], 张梅;冯立波;罗桂兰5.一种可应用于WLAN的高隔离度双频MIMO天线设计 [J], 严冬;郭琪富;程威;李杰;胡安沙因版权原因,仅展示原文概要,查看原文内容请购买。
宽带Fabry-Perot谐振腔天线及可重构技术在其中的应用
宽带Fabry-Perot谐振腔天线及可重构技术在其中的应用宽带Fabry-Perot谐振腔天线及可重构技术在其中的应用引言随着无线通信技术的飞速发展,大容量、高速率和高效能的通信系统已成为迫切需要满足的需求。
在通信系统中,天线作为信息传输的重要组成部分起着至关重要的作用。
随着频段的增多,天线的带宽要求变得越来越高。
而传统的天线技术面临着狭窄带宽、低效能和不适应多频段等问题,因此需要引入新的技术来满足这些需求。
一、Fabry-Perot谐振腔原理Fabry-Perot谐振腔技术是一种基于光频率选择性的原理,利用介质的强烈反射和干涉现象来实现高效的带宽扩展。
它由两个平行的反射面组成,之间填充着一种介质(例如气体、液体或固体)。
当入射信号与介质界面发生反射和干涉时,只有特定的频率得到放大,其他频率则被抑制。
这种选择性使得Fabry-Perot谐振腔天线能够在特定频带内实现高增益和低副瓣。
二、宽带Fabry-Perot谐振腔天线设计及特点宽带Fabry-Perot谐振腔天线的设计需要考虑多个因素,包括谐振腔长度、材料选择、反射面的设计等。
一般来说,谐振腔长度越长,频率选择性越强,带宽越窄。
因此,在设计宽带Fabry-Perot谐振腔天线时,需要针对不同的应用需求调节谐振腔的长度。
材料的选择也是关键因素,介质的折射率决定了谐振腔的频率选择性。
选择合适的材料可以实现更宽的带宽。
反射面的设计也很关键,设计高反射率的反射面可以增加天线的增益和带宽。
宽带Fabry-Perot谐振腔天线具有以下特点:1. 宽带性能:相比传统天线,宽带Fabry-Perot谐振腔天线具有更大的带宽,可以覆盖更多的频段。
2. 高增益:Fabry-Perot谐振腔技术可以实现高增益,提升通信系统的传输距离和质量。
3. 低副瓣:谐振腔的设计可以有效减少副瓣干扰,提高通信系统的抗干扰能力。
4. 紧凑设计:相比传统的天线结构,Fabry-Perot谐振腔天线可以通过调整谐振腔的长度来适应不同的频率,使得设计更为紧凑。
一种双环型宽频印制微带天线的设计与仿真
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全金属Fabry-Perot谐振腔天线
全金属Fabry-Perot谐振腔天线易先进;陈星【期刊名称】《空间电子技术》【年(卷),期】2024(21)3【摘要】为实现远距离微波无线能量传输,发射天线应具有耐受大功率、高增益、低损耗和结构简单等优点。
针对以上需求,文章设计了一款全金属结构的Fabry-Perot谐振腔天线。
整个天线包含全金属腔体,波导馈口和双层金属栅格覆盖层。
覆盖层的尺寸为3λ_(0)×3λ_(0),λ_(0)为对应的工作波长。
每一层金属栅格都包含9×9个单元。
所设计的双层覆盖层可以看作是一种电磁带隙结构,通过优化双层金属栅格单元的厚度和间距,实现了工作频段的宽带化,仿真结果表明其在9.72GHz~10.3GHz之间实现了插入损耗小于3dB的宽频带传输特性。
通过电磁带隙结构对馈源辐射出来的微波进行幅度和相位的修正实现增益的提高,仿真结果表明:不加载双层覆盖层时该天线的增益为9.7dBi,加上覆盖层之后增益提高到了17.76dBi。
为了验证上述设计和仿真,加工制作了一款全金属结构Fabry-Perot谐振腔天线,实测结果表明:该谐振腔天线在10GHz实现了17.31dBi的高增益,同时在9.51GHz~11.42GHz之间获得了回波损耗大于10dB的阻抗带宽。
【总页数】5页(P67-71)【作者】易先进;陈星【作者单位】中国电子科技集团公司第十研究所;四川大学电子信息学院【正文语种】中文【中图分类】V443;TN253【相关文献】1.基于人工磁导体表面的低剖面Fabry-Perot谐振腔天线设计2.加载分形EBG地的低剖面Fabry-Perot谐振腔天线设计3.高增益Fabry-Perot谐振腔锥状波束天线4.高增益Fabry-Perot谐振腔锥状波束天线5.带内低RCS的高增益宽带Fabry-Perot谐振腔天线因版权原因,仅展示原文概要,查看原文内容请购买。
基于开口环谐振器的小型化射频识别标签天线
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关键词 : 射频识别; 标签天线; 口 开 环谐振器
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一款双频双宽带双圆极化Fabry
现代电子技术Modern Electronics Technique2023年11月1日第46卷第21期Nov. 2023Vol. 46 No. 210 引 言随着信息技术的迅猛发展,空天地海一体化通信系统已经成为未来通信网络的发展趋势,卫星通信具有覆盖范围广、不受地理条件限制等优点,其作为天基通信的重要组成部分和未来6G 网络技术发展的重要方向,已经成为学术界研究的热点[1]。
天线作为卫星通信系统的关键组成部件之一,要求具有宽带宽、高增益、圆极化和结构简单、易于集成等特性。
由于法布里⁃珀罗(Fabry Perot, FP )谐振腔天线具有增益高、馈电简单的特性,自从其诞生以来便受到了学术界的广泛关注[2]。
FP 天线具有馈电结构简单、增益高的优点,近年来学术界对于FP 天线的双频段工作、宽带性能以及如何实现圆极化辐射做了大量研究工作,其在卫星通信系统中有良好的应用潜力。
对于FP 天线的双频工作特性[3⁃5],可采用频率选择表面(Frequency Selective一款双频双宽带双圆极化Fabry⁃Perot 谐振腔天线吕 军1, 钟选明2(1.国能包神铁路有限责任公司, 内蒙古 鄂尔多斯 017000;2.成都交大运达电气有限公司, 四川 成都 610000)摘 要: 文中设计了一款双频双宽带双圆极化的法布里⁃珀罗(FP )谐振腔天线。
传统的FP 天线具有高增益特性但是难以实现宽带及双频带工作,为了改善其性能,提出一种具有双频正相位梯度的部分反射表面,利用其正相位梯度特性弥补电磁波频率升高带来的空间相位变化,从而在较宽的带宽内满足FP 天线的谐振条件以实现宽带辐射。
通过加载寄生贴片以及缝隙耦合馈电的方式设计宽带圆极化馈源,并且采用人工磁导体结构替代传统的金属地板,在同一谐振腔高度下满足两个频段的谐振条件,简化了双频FP 天线的结构。
全波仿真结果表明,所提出的FP 天线3 dB 轴比带宽分别为10.1%和13.8%,峰值增益达到12.45 dBi 和11.9 dBi ,3 dB 增益带宽分别为11.5%和14.8%。
一种应用于无源感知系统的Fabry-Perot谐振腔天线[发明专利]
专利名称:一种应用于无源感知系统的Fabry-Perot谐振腔天线
专利类型:发明专利
发明人:王夫蔚,魏周朋,牛思莹,焦文丽,丁泊凯,陈晓江,房鼎益
申请号:CN202110606544.2
申请日:20210528
公开号:CN113471676B
公开日:
20220603
专利内容由知识产权出版社提供
摘要:本发明公开了一种应用于无源感知系统的Fabry‑Perot谐振腔天线,包括馈源微带天线和覆盖层,所述覆盖层由单元结构周期性排列而成,其覆盖层位于馈源微带天线的正上方,馈源微带天线包括馈源微带天线介质基板和馈源,馈源微带天线介质基板的下表面为铜质地板,其上表面为刻蚀形成的铜箔辐射贴片,即形成馈源。
本发明设计的Fabry‑Perot谐振腔天线尺寸为
220mm*220mm*48.5mm,增益在天线正上方达到最大,仿真值为11.56dB。
申请人:西北大学
地址:710127 陕西省西安市长安区学府大道一号
国籍:CN
代理机构:西安研创天下知识产权代理事务所(普通合伙)
代理人:梁宝龙
更多信息请下载全文后查看。
一种Fabry_Perot谐振器天线_顾莹莹
Ne w Application新应用56一、引言微带贴片天线具有印刷电路工艺的全部优点,体积小、剖面低、制造成本低、易于结构共形、适合与电路集成,因而得到了广泛的应用。
然而,传统的贴片天线是高Q 值的谐振结构,导致了其频带较窄,一般在5%以下。
此外,由于金属损耗和介质损耗的存在,使得贴片天线的效率较低,功率容量小。
Fabry-Perot 谐振器最初应用在光学领域,其可以有选择地传播或反射特定波长的电磁波。
鉴于Fabry-Perot 谐振器结构对电磁波传播具有选频的作用,满足谐振条件的电磁波穿透Fabry-Perot 谐振器后能同相叠加而增强。
将此Fabry-Perot 谐振器结构应用在天线系统中,也能明显提高天线的辐射定向性。
二、Fabry-Perot 谐振器结构在印刷天线上方加上盖板,构成Fabry-Perot 谐振器结构,能够有效增大天线的增益。
若选用一层介质型盖板结构,通常盖板与天线的间距取为λ/2,此时为了满足谐振条件,介质盖板的厚度应为λg /4(反射盖板的最佳值[1])。
然而,在实际应用中,可选用的介质板厚度受限于产品规格,有时不能完全满足谐振要求。
此外,如果在较低的频段上设计反射盖板,其λg /4的尺寸是不切实际的。
因此考虑将单层较厚的介质盖板改换为两层有空气间隔而厚度较薄的介质盖板[2]。
三、宽频带馈源辐射器馈源辐射器用于激励F-P 谐振器,它的性能直接影响谐振器天线的特性。
为了实现较宽的频带特性,需要选择宽频带的馈源辐射器。
单层单贴片的宽带微带天线结构能够保证天线的低轮廓,同时当用于阵列时不会引入栅瓣。
Huynh 和Lee [3]报告了U 型缝隙微带矩形贴片的测量结果,证明了其宽带特性。
此后,Lee 等[4]研究了一系列中心频率在4.5GHz左右的U 型缝隙天线,同样证明了其宽带性能,并分析了不同参数对天线性能的影响。
该天线结构可以实现宽频带或双频带性能,增益大约为7dBi。
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I.J. Wireless and Microwave Technologies, 2015, 2, 1-11Published Online April 2015 in MECS()DOI: 10.5815/ijwmt.2015.02.01Available online at /ijwmtFractal Peano Antenna Covered by Two Layers of Modified RingResonatorAmmar Nadal Shareef a, Amer Basim Shaalan b*a Department of General Sciences, Al-Muthanna University,Samawa, Iraqb Physics Department, Al-Muthanna University,Samawa, IraqAbstractNegative index of refraction has attracted a great attention in literatures. These materials are artificial structures named metamaterials has characteristics not found in nature. Microstrip antennas covered by metamaterial are very interesting areas of study. In this paper fractal Peano shape antenna is proposed and covered by two layers of modified ring resonator. The results show an enhancement in Reflection Coefficients, gain, and directivity.Index Terms: Metamaterials, left handed materials, split ring resonators, negative refractive index, fractal antennas.© 2015 Published by MECS Publisher. Selection and/or peer review under responsibility of the Research Association of Modern Education and Computer Science1.IntroductionFew years ago, there is an interest among electromagnetic research groups in the study of Metamaterials as they provide electromagnetic properties not find in natural materials [1]. Simultaneously negative permeability and permittivity over certain frequency range are the most important properties of interest. Veselago while studying this type of materials in 1968 [2], he mentioned to some unique properties like negative refractive index and backward waves. Split ring resonator is regarded as the most known designs to get negative permeability. Several different shapes of split rings are published in literatures to achieve the requirement of negative permeability [3-5].Classical microstrip patch antennas are the most popular antennas because of several advantages such as low profile, light weight and low cost of fabrication. The addition of a superstrate layer over microstrip patch antenna (MPA) has been reported to enhance antenna gain and radiation efficiency [6-9]. Several configurations of superstrates were used to improve antenna radiation properties, such as dielectric slabs [10], electromagnetic band gap (EBG) structures [11], highly-reflective surfaces [12], and the most recently artificial magnetic superstrates [13].* Corresponding author.E-mail address: ame72r@Fractal shapes are utilized in antenna design to improve its parameters. In this paper, we introduce modified ring design by adding more spaces to the open side and use it as a superstrate of two layers over fractal antenna shape. This configuration is shown in Fig.1. HFSS software code which is based on finite element modeling was used to calculate S - parameters. Notable enhancement of gain and directivity obtained from this model of fractal antenna shape.This paper is containing five sections. First section is representing the introduction of the work. Ring design is discussed in section two. Section three explain the fractal antenna design. Results and discussion are presented in section four. Finally, conclusion of this work is presented in section five.Fig. 1. Configuration of Superstrate Over fractal Antenna Shape2.Ring DesignDimensions of single unit cell are 4 mm side length, 0.4 mm width of side, 0.4 mm width of the middle space and 0.2 mm width of extra spaces. We use three and five extra spaces in our design (SRR1, SRR2, SRR3). Three different unit cells are simulated in a waveguide to calculate scattering parameters. Meta-cover (MTM) configuration is shown in Fig.2.Fig.2. Meta-Cover configuration and unit cell design (SRR1, SRR2, SRR3)Unit cells are etched on FR4 substrate (εr = 4.4) of 0.25 mm thickness. Separation distance between cells is 1.4 mm. 225 cells are distributed to cover the area above Peano antenna. Relative permittivity, relative permeability and refractive index are determined using Nicolson-Ross-Weir approach [14].(1)(2)√ (3) Where(4)(5)⁄ (6) Where ωis the radian frequency, d is Substrate thickness, and n is the refractive index3.Fractal Antenna DesignIn this section, description of fractal shape generation is presented. The starting shape of the antenna is a square has side length equals to 28.5 mm. The generator is a second iteration of Peano curve. The generator is applied to each side of the square to get the final fractal shape of the antenna as shown in Fig.3. The generator is a straight line divided into three segments, the middle one also divided into three segments. Keeping the middle one and removing its neighbors, and then connecting the middle segment with others by using tuning length called indentation width [15]. The shape we get from this process is the generator as shown in Fig.4. Patch antenna etched on substrate of dimensions 60 mm x 60 mm x 1.6 mm. Substrate material is FR4 with relative permittivity ().Fig.3. Fractal Peano Antenna Shape(a)(b)Fig.4. Generator of Fractal Peano Antenna4.Results and DiscussionTwo layers of modified rings are designed to be superstrate cover over peano patch antenna. We introduce different shapes of rings. The rings have three and five extra spaces. Calculations shows that the best distance of separation between first cover and the patch is 15 mm. The second cover is placed at 15 mm above the first one. Fig. 5 shows the resonance frequency of each model of the rings. Fig. 6 shows relative permittivity, relative permeability and refractive index versus the frequency. From these figures, we can see the resonances and negative refractive index lies in the same range of frequency. The bandwidth of negative refractive index is increased when extra spaces are used in the design. Another way to prove left-handed behavior of the material is dispersion diagram. Fig.7 shows the dispersion diagram of SRR1, SRR2, and SRR3 designs. From this figure, we can see the backward radiation of the rings, which is started at the resonant frequency of each ring. The refractive index may has negative values without the simultaneous negative values of real permeability and permittivity (μ' and ε'). The condition in [16] is utilized to get negative refractive index as seen in (7).(7) Where μ',ε' are real part of permeability and permittivity and μ'',ε'' are imaginary part of permeability and permittivity. This condition is plotted versus frequency in Fig.8. Calculations of S-parameters of fractal antenna shape shows a multi band behaviour of this antenna model. It resonates at 7.6 GHz, 8.2 GHz, 10 GHz, and 11.17 GHz. Fig.9 shows the multiband behaviour of the antenna with meta-cover and without it. Gain and directivity of Peano antenna without meta-cover are listed in Table1. Shapes of radiation patterns are shown in Fig.10. By adding the two layers of meta-cover above the antenna, we obtain enhancement of gain and directivity. Enhancement of gain reach to 11.7 dB at 8.2 GHz. Results of gain and directivity are listed in Table 2. Fig.11 shows radiation pattern shapes of fractal antenna with meta-cover. Fig.12 shows three-dimensional far field of the antenna.Fig.5. Resonance frequency of SRR1, SRR2, SRR3(a). Permittivity(b). Permeability(c). Refractive IndexFig.6. (a) Relative Permittivity (b) Relative Permeability (c) Refractive index versus FrequencyFig.7. Dispersion diagramFig.8. μ'ε'' + μ''ε' versus frequencyFig.9. S11versu Frequency of Fractal Antenna without and with meta-cover(a)(b)(c)(d)Fig.10. Radiation Pattern of Fractal Antenna without meta-cover (a) frequency = 7.6 GHz (b) frequency = 8.2 GHz (c) frequency = 10 GHz (d) frequency = 11.17 GHz(a)(b)(c)(d)Fig.11. Radiation Pattern of Fractal Antenna with meta-cover (a) frequency = 7.6 GHz (b) frequency = 8.2 GHz (c) frequency = 10 GHz (d) frequency = 11.17 GHz(a)(b)Fig.12. Three-dimensional far field antenna (a) with mtm (b) without mtmTable 1. Fractal Antenna Parameters without meta-coverFrequency (GHz)Gain (dB) Directivity (dB) S11 (dB)7.6 2.3 7.9 -13.98.2 3.3 8.6 -1310 4.1 8 -15.211.17 5.7 8.5 -14.5Table 2. Fractal Antenna Parameters with meta-coverFrequency (GHz) Gain (dB) Directivity (dB) S11 (dB)7.6 6.7 9.2 -12.78.2 11.7 9.2 -17.310 9.3 13.7 -14.711.17 5.7 9.2 -15.85.ConclusionsIn this paper we use modified rings as two layers of meta-cover over fractal Peano shape antenna. Distance between antenna and first cover is 15mm. The two layers are separated by 15 mm. Results shows best enhancement in gain and directivity at these distances. enhancement of antenna parameters is related to the extra spaces added to the unit cell of meta-cover. This model is very useful in point-to-point communication and meta-cover can protect the antenna from environment hazards in addition to enhancing antenna parameters. This model is currently under fabrication. Two other models are currently under investigation and will be discussed in future publications.References[1]Veselago V., Braginsky L., Shklover V., and Hafner C., “Negative Refractive Index Materials,”Journalof Computational and Theoretical Nanoscience, 2006, Vol.3, pp.1–30.[2]Veselago V. G., “Electrodynamics of substrates with simultaneously negative values of and,”Sov.Phys. Usp., 1968, Vol. 10, No. 4, pp.509-514.[3]Balmaz P. and Martin O., “Electromagnetic resonances in individual and coupled split-ring resonators,”JOURNAL OF APPLIED PHYSICS, V. 92, no. 5 pp. 2929-2936.[4]Wu B., Li B., Su T., and Liang C., “Study on Transmission Characteristic of Split-ring ResonatorDefected Ground Structure,” PIERS ONLINE, 2006, Vol. 2, no. 6, pp. 710-714.[5]Bimal G., Singhal P., “Improving Principle Design of Rectangular SRR based Metamaterial Structurewith Negative μ and ε for Characteristics of Rectangular Microstrip Patch Antenna,”International Journal of Engineering Research, Vol.1, no.2, pp. 38-44.[6]Wu, B-I, Wang W., Pacheco J., Chen X., Grzegorczyk T., and Kong J., “A study of using metamaterialsas antenna substrate to enhance gain, ”Progress in Electromagnetic Research, PIERS 51, 2005, pp.295-328.[7]Garg B., Tiwari R., Kumar A., and Chitransh T., “Design of factored …X‟ shaped metamaterial structurefor enhancement of patch antenna gain,”International Conference on Communication Systems and Network Technologies 2011.[8]Sarkar D., Saurav K., and Vaibhav K., “Design of a Novel Dual-band Microstrip Patch Antenna forWLAN/WiMAX Applications Using Complementary Split Ring Resonators and Partially Defected Ground Structure, ”Progress In Electromagnetics Research Symposium proceedings, Taipei, March 25-28, 2013.Fractal Peano Antenna Covered by Two Layers of Modified Ring Resonator 11 [9]Foroozesh A., and Shafai L., “Effects of artificial magnetic conductors in the design of low-profile high-gain planar antennas with high permittivity dielectric superstrate,”IEEE Antenna Wireless Propagat.Lett., 2009, vol. 8, pp. 10 –13.[10]Vettikalladi H., Lafond O., and Himdi M., “High-efficient and high-gain superstrate antenna for 60-ghzindoor communication,”IEEE Antenna Wireless Propagat. Lett., 2009, vol. 8, pp. 1422–1425.[11]Attia H., and Ramahi O. M., “EBG superstrate for gain and bandwidth enhancement of microstrip arrayantennas,” in Proceeding of IEEE AP-S Int. Symp. Antennas Propagation, San Diego, CA, pp. 1–4, 2008.[12]Foroozesh A., and Shafai L., “Investigation into the effects of the patch type fss superstrate on the high-gain cavity resonance antenna design, ”IEEE Trans. Antennas Propagat., 2010, vol. 58, no. 2, pp. 258–270.[13]Attia H., Yousefi L., Suwailam M. M., Boybay M. S., and Ramahi O. M., “Enhanced-gain microstripantenna using engineered magnetic superstrates, ” IEEE Antenna Wireless Propagat. Lett., 2009, vol. 8, pp. 1198– 1201.[14]Ziolkwski R. W., “Design, fabrication, and testing of double negative metamaterials,”IEEETransactions on Antennas and Wireless Propagation, 2003, Vol.51, No. 7, 1516-1529.[15]Barnsley M.F., “Fractals Every Where,”Academic press INC., NewYork, 1993.[16]Nguyen T. T., Lievens1 P., Lee Y. P., and Vu D. L., “Computational studies of a cut-wire pair andcombined metamaterials,” Advances in Natural Sciences: Nanoscience and Nanotechnology. 2011, Vol.2, No. 3, p: 9.Author(s) ProfilesAmer Basim Shaalan was born in Baghdad, Iraq in May of 1972. He received his B.Sc,M.Sc and PhD degrees in 1994, 1997 and 2002 respectively in Physics from Al-Mustansiriyah University, Iraq. From 2005-2013, he was head of Physics Department inAl-Muthanna University, Iraq. He was Assistant Prof. since 2008. Sabbatical atPhyladelphia University, Jordan in 2010. His interest area is Fractal antenna and Lefthanded materials.Ammar Nadal Shareef was born in Samawa, Iraq in June of 1983. He received his B.Scdegree in Physics in 2006 from Al-Muthanna University, Iraq. and M.Sc degrees in 2009in Physics from Basrah University, Iraq. He is currently PhD student. From 2009, he waswork in General Science Department in Al-Muthanna University, Iraq. His interest area isFractal antenna and metamaterial.How to cite this paper: Ammar Nadal Shareef, Amer Basim Shaalan,"Fractal Peano Antenna Covered by Two Layers of Modified Ring Resonator", IJWMT, vol.5, no.2, pp.1-11, 2015.DOI: 10.5815/ijwmt.2015.02.01。