A Modified Sierpinski Carpet Fractal Antenna for Multiband Applications

The sudden growth in wireless communication area has increased the requirements of compact integrated antennas. This paper describes the design of Modified Sierpinski Carpet Fractal Antenna which resonates at six frequencies 4.825, 5.455, 6.265 GHz and 6.805, 8.02 and 9.145 GHz. Different performance parameters like radiation pattern, gain, Voltage Standing Wave Ratio, return losses are observed at all the frequencies. The FR4 glass epoxy with relative permittivity 4.4 and height 1.6 mm is used as substrate material. Antenna is fed by coaxial probe feed and simulated using ANSYS/ANSOFT HFSS V13 software. Proposed antenna has simple structure. Investigation is done between 1 and 10 GHz frequencies. The proposed antenna is fabricated and tested on the Vector Network Analyzer. The measured and simulated results of proposed antenna are compared and are found to be good agreement with each other.

     

A Hybrid Fractal Metamaterial Inspired Multiband Antenna for Wireless Applications

Wireless Personal Communications - In this paper a multiband (hepta-band) antenna loaded with hybrid fractal structures and metamaterial cell (SRR/CSRR) is proposed to cover the wireless...     

抗干扰设备中的Sierpinski分形微带天线

设计了一种新型Sierpinski分形天线,通过对接地板开槽和改进天线结构,使天线满足在多频带要求下,实现了3.65～5.35GHz（37.5%）的频率缺口的功能,大大提高了天线的抗干扰性。利用HFSS仿真和实验测试表明：天线的远场辐射方向图、回波损耗均满足天线设计要求,并且分形特有的尺寸缩减性实现了天线的小型化。     

改进型Sierpinski三角形分形多频天线研究

分形天线可以实现多频工作和尺寸减缩,在军用与民用方面都有着很大的发展潜力.研究了一种新结构形式的改进型Sierpinski分形天线,与普通结构相比,其可以通过调节各个三角形的高度比例来调整频比,且结构简单,加工制作更容易.仿真结果验证了改进型Sierpinski多三角形天线的多频特性.     

改进型Sierpinski分形微带天线仿真

将HFSS高频仿真软件对不同张角下的二阶Sierpinski分形天线进行仿真,得到不同情况下的回波损耗参数和方向图。Sierpinski分形天线具有多频段的特性,由其自相似分形结构决定。在一定角度下的二阶Sierpinski分形天线具有双频特性,可以广泛应用于卫星通信和移动通信。     

Sierpinski分形天线特性分析

Sierpinski分形天线的结构具有自相似性,从而天线具有良好的多频带特性。文中主要研究了Sierpinski分形天线频带位置随天线张角和比例因子变化的一般规律,并简要的分析了Sierpinski分形天线阵,绘出了其远场方向图,讨论了其低副瓣特性。     

Modified Sierpinski Fractal Monopole for ISM-Bands Handset Applications

Antenna design is a mature field of research; it is therefore rare that a new approach arises in view of the traditional methods. In the past antennas had simple form based on Euclidean geometry. Fractal antennas do not follow this design. Their complex structure is built up through replication of a base shape. The purpose of this research is to explore fractal element antennas, through simulation and design experimentation. This research revealed unexpected results, which provided additional insight into these unique structures. Results of MoM and FDTD simulation methods as well as measurements of physical models of the circuit- and field-antenna parameters are presented and discussed. Measurements well confirmed simulation.     

基于领带结Sierpinski分形结构的RFID标签天线

基于三角形Sierpinski微带分形贴片,提出了一种新型的小尺寸领带结RFID标签天线设计。通过仿真,给出了该分形天线的端口特性,同时给出了该领带结型Sierpinski标签天线的谐振频率、方向图以及天线效率。结果表明,采用不同维数的分形结构,可以实现多频段的工作特性,因而该天线可以很方便地应用于RFID电子标签中。     

具有陷波特性的改进Sierpinski分形超宽带天线

为了避免WLAN窄带通信系统对超宽带通信系统的干扰,该文提出一种具有陷波特性的改进 分形超宽带天线。天线的辐射单元是改进的 阶 分形结构,通过采用共面波导馈电技术以及增加 分形的迭代次数,可有效展宽天线的带宽,从而实现覆盖 频段的宽频特性。在分形贴片上增加两个对称的L型开路枝节,实现了 频段的双陷波特性,能有效抑制WLAN频段对超宽带通信系统的干扰。天线的尺寸较小,仿真和实测结果表明天线可广泛适用于各种UWB通信系统。     

一种新型加载Sierpinski垫片天线的设计

提出一种新型分形结构加载的Sierpinski垫片天线。该天线采用新型加载技术并充分利用了此新型结构的空间自填充能力。结果表明,此新型分形结构加载的Sierpinski垫片天线比Koch分形加载更能缩减天线的尺寸,并且能降低谐振频率,具有宽频带特性,可以实现Sierpinski分形天线的小型化、多频段特性。     

Design and Analysis of Multiband Fractal Antenna for MIMO/Diversity Applications

In this article a modified hybridized fractal geometry i.e., fractal antenna is proposed for Multiple Input Multiple Output (MIMO) applications. These geometries are based on Minkowski curves and Koch curves located around the boundaries of the microstrip patch of rectangular-shaped patch. The hybridized model for fractal geometry is designed and analyzed on an FR4 substrate having a thickness of 1.47 mm for the Industrial, Scientific, and Medical (ISM) frequency band. But due to the proposed fractal geometry, it resonates at three bands (2.45 GHz, 3.67 GHz, and 5.88 GHz) and it is covering the ISM band from 2.42 GHz to 2.48 GHz with a VSWR value is 1.48. Further, a 2?×?2 antenna for MIMO application is proposed by considering identical antenna elements placed in parallel on the same substrate. MIMO antenna resonates at three frequencies as same as single antenna elements and covering the same operating bands. The two elements of MIMO confguration are simulated for various sets of distance values, and optimized distance is obtained 18 mm at which a proposed antenna provides low mutual coupling value, low Envelope Correlation Coefficient (ECC), and high diversity and peak gain. The calculated values of ECC and diversity gain are 0.0002 and 10 dB, respectively which satisfy the criteria of MIMO application. The design has been experimentally validated and an appropriate similarity of experimental and simulated results is achieved.

     

Circular Fractal Antenna Design with Inscribed Square for Ultra Wide Band Applications

Journal of Communications Technology and Electronics - In this article, an ultra-wide band circular fractal antenna inscribed with square is presented. The prototype of the antenna is fabricated on...     

An Optimal Design of Fractal Antenna with Modified Ground Structure for Wideband Applications

This paper premeditates an optimal design of fractal antenna with modified ground structure for wideband applications. The proposed antenna has been designed by taking numerous iterations started from 0th to 3rd. To attain the wideband characteristics, the partial ground plane has been introduced in the 3rd iteration, and the length of the ground plane has been varied to enhance the bandwidth. The maximum value of bandwidth has been adorned in the final iteration as 1.88 and 0.20 GHz. Further, this bandwidth has been improved and embellished as 2.48 GHz within the frequency range of 3–6 GHz by employing horizontal and vertical extensions in the partial ground plane. Antenna is simulated by using HFSS and performance parameters of antenna like return loss (S_11?≤???10 dB), gain and radiation efficiency are in the acceptable limits. The maximum value of gain is reported as 5.1 dB and radiation pattern is also omnidirectional. The proposed antenna is useful for the wireless applications as WiMAX (3.4–3.69 GHz) and WLAN (5.15–5.35 and 5.72–5.82 GHz) Simulated and experimental results are also juxtaposed and found in good agreement with each other.     

基于Matlab和矩量法的Sierpinski分形天线仿真与分析

Sierpinski分形天线的结构具有自相似性,从而使其具有良好的多频性.文章基于Matlab和矩量法对张角为60°、分形阶为2的sierpinski蝴蝶结分形天线进行了仿真,计算并分析了输入电阻、输入阻抗、反射系数和增益等天线特性,分别从仿真和实测角度比较了该天线在张角不同的情况下的谐振频率分布,得到了谐振点频率会随着天线张角变化而变化的结论,为设计特定频率下工作的分形天线提供了可能.     

Design and Analysis of a Fractal Antenna Using Jeans Material for WiMax/WSN Applications

This paper presents a novel approach in designing fractal antennas operating at 2.45 GHz. Mainly focuses on design and simulation of a combination of Koch and Sierpinski fractal antenna with jeans as substrate material with dielectric constant 1.6 up to 2nd iteration. The design of antenna presented here can radiate at 2.45 GHZ, 3.64 GHZ, and 4.06 GHz frequencies with a reflection coefficient less than  ? 10 dB, VSWR between 1 and 2 and enhancement in bandwidth up to 200 MHz. This antenna has been simulated using CADFEKO software, fabricated and tested on VNA and has been observed that there is good conformity between simulation and experimental results. Besides that, Fractal antenna using jeans material as substrate for WiMAX/WSN Application at S and C frequency bands is small in size, flexible, less costly and low profile multiband antenna.

     

分形天线的特性与应用

分形天线是分形几何和天线技术交叉的产物。与传统天线比较,在性能保持相近的情况下,它表现出两个突出的优点:能够在多频段下工作、可以缩小天线尺寸。本文以Sierpinski Gasket天线为例,介绍了它的多频段特性;以Koch分形天线为例,说明了分形天线在缩小天线尺寸方面的优势。介绍了分形天线在UHF频段的应用现状,指出了进一步研究分形天线需要解决的若干问题。     

RFID分形阅读器天线设计

研究了不同阶数的Minkowski分形微带贴片天线的性能,给出了一种双层2阶Minkowski分形阅读器天线,仿真结果表明,天线在谐振频率点处具有良好的性能,且尺寸大小为30mm×30mm,与普通的方形贴片天线相比,其面积大约减少了43．75％,宽度减少了25％,具有较好的尺寸缩减特性,天线的性能和尺寸能满足手持RFID阅读器的要求。该天线设计具有结构简单、易于制作等特点,适合用于RFID阅读器天线的小型化设计。     

Hybrid Fractal Antenna Using Meander and Minkowski Curves for Wireless Applications

Wireless Personal Communications - This paper describes a novel design of Minkowski and Meander curves based hybrid fractal antenna for mobile devices used for communication in delay tolerant...     

Defected Ground Based Fractal Antenna for S and C Band Applications

Wireless Personal Communications - Defected ground based modified rectangular fractal patch antenna for mobile devices communication in Delay Tolerant Networks, Wireless sensor networks and Mobile...     

分形天线--一种新颖的天线小型化技术及其应用

分形几何具有重要的特性，即自相似性和分数维，可以成功的应用于天线的设计。本文主要介绍了分形的基本概念，并对典型的分形天线及其小型化原理进行了简要介绍。