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1.
Sreejith M. Nair Shameena V.A Nijas C.M C.K. Aanandan K. Vasudevan P. Mohanan 《国际射频与微波计算机辅助工程杂志》2013,23(1):40-46
A high‐efficiency and high‐gain slotline fed directive dipole antenna is developed for microwave applications. The antenna offers an average gain of 7.9 dBi with a front to back ratio better than 20 dB and a cross polar level better than ?20 dB. Design equations of the antenna are developed and validated on different substrates. The simulation and experimental results show that the proposed antenna exhibits high gain and robust radiation patterns in the entire frequency band. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013. 相似文献
2.
In this article, a broadband coplanar waveguide (CPW) to rectangular waveguide power divider using the dipole slot is proposed. The power divider consists of an input CPW port and two output rectangular waveguide ports. The CPW to rectangular waveguide power divider using the dipole slot has a return loss larger than 15 dB and an insertion loss equal to 3.08–3.27 dB in the whole X‐band (8.2–12.4 GHz). Furthermore, to broaden the bandwidth, the dipole slot is replaced by the bow‐tie slot. The CPW to rectangular waveguide power divider using the bow‐tie slot yields a return loss larger than 16 dB and an insertion loss equal to 3.05–3.29 dB from 8 to 13 GHz, which exceeds the X‐band. To verify our design, power dividers that use the dipole slot or the bow‐tie slot are fabricated and measured. The measurement results of both power dividers are in good agreement with the simulation results. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013. 相似文献
3.
A novel compact coplanar strip fed dipole antenna with a step cut suitable for ultrawideband (UWB) application is developed. The antenna is evolved from an open ended slot line by symmetrically etching out two rectangular metallic parts from its upper inner corners. The antenna has ?10 dB reflection coefficient from 3.1 to more than 12 GHz that covers the Federal Communication Commission (FCC) specified UWB frequency range. From the simulation and experimental studies, it is found that the proposed antenna delivers moderate gain and stable radiation patterns over the operating band. Time domain analysis on the proposed antenna has been conducted and was found that the antenna can be used for UWB applications. The proposed antenna occupies a compact size of 28.5 × 10 × 1.6 mm3. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:665–672, 2014. 相似文献
4.
In this communication a 2 × 2 dielectric resonator antenna (DRA) array is proposed with a wideband frequency response. An air bridgeless coplanar waveguide (CPW) power divider network is first time used to feed the 2 × 2 DRA array. Four rectangular DRAs are used as array element and exited in TE111 mode by four slots at the end of the CPW lines in the feed network. The straight CPW phase delay line in feed network is further meandered resulting an enhanced radiation performance. The proposed DRA array exhibits a wideband response with an impedance bandwidth of 16% while maintaining a stable broadside radiation pattern with the gain range from 8 to 9.4 dBi. The proposed design is fabricated and measured, reaching good agreement with simulation results. 相似文献
5.
This paper presents a novel ultra‐wideband (UWB) antenna printed on a 70 μm thick flexible substrate. The proposed antenna consists of a hybrid‐shaped patch fed by coplanar waveguide (CPW). The ground planes on opposite sides of the feeding line have different height to improve antenna bandwidth. Simulation shows that the proposed antenna maintain wide bandwidth when changing its substrate's thickness and dielectric constant, as well as bending the antenna on a cylindrical foam. The proposed antenna is fabricated in laboratory with a simple and low‐cost wet printed circuit board (PCB) etching technique. Measured bandwidths cover 3.06 to 13.58, 2.8 to 13.55, and 3.1 to 12.8 GHz in cases of flat state and bent with radii of 20 and 10 mm, respectively. Measured radiation patterns show the antenna is omnidirectional in flat and bent cases. 相似文献
6.
Sreejith M. Nair V. A. Shameena C. M. Nijas C. K. Aanandan K. Vasudevan P. Mohanan 《国际射频与微波计算机辅助工程杂志》2012,22(5):581-587
A printed slot line fed dual‐band coplanar dipole antenna having a dimension of 0.40λg × 0.20λg suitable for both 2.4 and 5.2 GHz (IEEE 802.11 b/g and 802.11 a) WLAN application is presented. The structure comprises of a slot line fed symmetrical L strips to achieve dual‐band operation. Design equations of the antenna are developed and validated on different substrates. The simulation and experimental results show that the proposed antenna exhibits good impedance match, gain, and stable radiation patterns in both the frequency bands. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2012. 相似文献
7.
Mohammad Alibakhshi‐Kenari Mohammad Naser‐Moghadasi Ramazan Ali Sadeghzadeh Bal Singh Virdee Ernesto Limiti 《国际射频与微波计算机辅助工程杂志》2016,26(3):217-225
This letter presents the experimental results of a novel planar antenna design which is synthesized using simplified composite left/right‐handed transmission‐line (SCRLH‐TL), which is a version of a conventional composite left/right handed‐transmission‐lines (CRLH‐TL), however, with the omission of shunt‐inductance in the unit‐cell. SCRLH‐TL exhibits a right‐handed response with nonlinear dispersion properties and a smooth Bloch‐impedance distribution. Arranged within the inner slot of the antenna are three smaller rectangular patch radiators. Each patch radiator is embedded with an E‐shaped notch, and located in the antenna conductor is a larger E‐shaped notch next to the 50‐Ω termination. The E‐shaped notches constitute SCRLH‐TL property. The gap in the slot between the smaller patches and the conductor next to the larger E‐shaped notch determines the impedance bandwidth of the antenna. The dimensions of the smaller patches determine the radiation characteristics of the antenna. The antenna is excited using a conductor‐backed coplanar waveguide transmission‐line. The antenna covers a bandwidth of 7.3 GHz between 0.7 GHz and 8GHz, which corresponds to 167.81%. In this band, the antenna resonates at 4.75 GHz and 7 GHz; the gain and radiation efficiency at these frequencies are 4 dBi—80% and 3.6 dBi—73%, respectively. The antenna's performance was validated through measurement. The antenna has dimensions of 0.0504λ0 × 0.0462λ0 × 0.0018λ0, where λ0 is free‐space wavelength at 700 MHz. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:217–225, 2016. 相似文献
8.
Qiang Chen Hou Zhang Lu‐chun Yang Hai‐peng Li Tao Zhong Xue‐liang Min Shi‐li Tan 《国际射频与微波计算机辅助工程杂志》2017,27(1)
A novel dual‐band, dual‐circularly polarized antenna is proposed and fabricated. The proposed antenna consists of an asymmetric U‐shaped slot and an inverted L‐shaped slot which are designed to excite two orthogonal E vectors with equal amplitude and 90° phase difference (PD), in addition, fed by a coplanar waveguide (CPW) Furthermore, a left‐hand circular polarization in the direction of z > 0 and a right‐hand circular polarization instead of the opposite direction both at the lower and upper bands are exhibited by the radiations of the antenna. Good agreement is achieved between the measurement and simulation, which indicates that a 10‐dB bandwidth of 38.75% from 2.56 to 3.8 GHz and 21.8% from 10.01 to 12.53 GHz, while a 3‐dB axial‐ratio bandwidth (ARBW) of 13.4% from 2.77 to 3.2 GHz and 9.23% from 10.25 to 11.25 GHz at two operation bands, respectively, are covered in the designed antenna. To explain the mechanism of dual‐band dual‐circular polarization, the analysis of magnetic fields distributions and a parametric study of the design are given. Meanwhile, compared to other recent works, a single layer structure, wider axial ratio and impedance bandwidths and a more compact size are the key features of the proposed antenna. 相似文献
9.
A compact slot antenna with an overall dimension of 30 × 30 × 1.6 mm3 is proposed for dual band applications. The radiating element is a hexagonal shape patch which protrudes from a Co‐Planar Waveguide (CPW) feed into a step shape slot. The slot is basically rectangular in shape and is extended by inserting rectangular cuts of different sizes on the ground plane around it. The ultrawide impedance bandwidth is achieved using asymmetric feed line along with extended rectangular cuts around the slot. For realizing the second band for personal communication system applications (near 1.9 GHz), a metallic stub of quarter wave length is attached at the top of the slot. The measured impedance bandwidth (for S11 < ?10 dB) is 110 MHz (1.86–1.97 GHz) for the first band and 9 GHz (3.0–12.0 GHz) for the second band. The antenna is further characterized by omnidirectional radiation patterns in the H‐plane, dumb‐bell shape radiation patterns in the E‐plane and a peak gain of 3–5 dBi over the ultrawideband. All the measured results are found to be in good agreement with the simulated results. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:243–254, 2015. 相似文献
10.
一种宽带天线的研究与设计* 总被引：1，自引：0，他引：1
为了满足宽带通信的需求,利用U形单极子天线和两个U形寄生辐射元的方法,设计了一种共面波导馈电的宽带天线,其阻抗带宽达到85%。所设计的天线印刷在尺寸为20 mm×30 mm×1.6 mm、介电常数为265的聚四氟乙烯介质基板上。为了满足无线局域网（WLAN）和全球互联微波接入（WiMAX）的工作需要,抑制不需要的信号,在U形单极子辐射元之间插入一条调谐微带线,产生一个陷波特性,使所设计的天线满足WLAN、WiMAX和低端UWB通信需求。利用高频结构仿真软件HFSS对影响天线性能的主要参数进行仿真、分析和优化,得到天线的优化尺寸,并对优化的天线进行制造和测试。实验结果表明,该天线比传统微带贴片天线性能有了较大的提高,证明了利用共面波导馈电和寄生技术设计宽带天线的可行性和有效性。 相似文献
11.
A new compact planar monopole antenna which covers an ultra wide bandwidth of ～147% from 2.96 to 19.43 GHz for S11 ≤ ?10 dB is presented. The proposed antenna has simple configuration and easily fed by using a 50 Ω microstrip line. The total size of the antenna is 30 × 26 × 1.6 mm3. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
12.
This article presents a comprehensive parametric study with experimental characterization of an inductively coupled CPW-fed slot antenna on a GaAs substrate for MMIC applications. The length, width, and feed inset of the antenna are varied and their influences on the input impedance, bandwidth, and gain are investigated. The parametric study reveals that the slot length is the prime factor for determining the resonant frequency, while the width is used for fine-tuning of resonant frequency and gain-bandwidth product. For the fixed slot dimensions, the feed inset tremendously affects both resonant frequency and input match. The manufactured antenna resonates at 22.4 GHz with a 6.1% impedance bandwidth, 2% gain bandwidth, 2.5-dBi boresight gain, and 5-dB front-to-back (F/B) radiation level. The antenna exhibits bidirectional radiation patterns with almost omnidirectional patterns in the E-plane and a wide beamwidth of 84° 3-dB beam width in the H-plane. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14, 4–14, 2004 相似文献
13.
In this article, a wideband circularly polarized (CP) dielectric resonator (DR) over an asymmetric‐slot radiator based hybrid‐DR antenna is proposed with bi‐directional radiation characteristics. Bi‐directional CP radiation of the dual sense is obtained using a rectangular‐DR over asymmetric‐rectangular‐slot radiator with L‐shaped feed line. The asymmetric‐slot radiator feed by L‐shaped stub with the coplanar waveguide is used for generating two orthogonal modes, namely TE x δ11 and TEy1δ1 in the combined (rectangular‐DR and asymmetric‐slot radiator) hybrid‐DR antenna, which is verified by the distribution of electric field inside the rectangular DRA. The measured reflection coefficient bandwidth (S11 < ?10 dB) and axial ratio (AR) bandwidth (AR < 3 dB) of the hybrid‐DR antenna are 80.5% (1.87‐4.39 GHz) and 43.8% (1.75‐2.73 GHz), respectively. The antenna radiation is in the broadside (θ = 0°, ? = 0°) direction as well as in the backside (θ = 180°, φ = 0°) direction with equal magnitudes in both the directions. Right‐handed and left‐handed CP waves are achieved respectively, in the boresight (+Z) and the backside (?Z) directions. The proposed CP hybrid‐DR antenna gives an average gain of 3.55 dBic and radiation efficiency of 95.0% in both directions. The proposed antenna covers various wireless useful bands such as ISM 2400 band, Wi‐Fi, Bluetooth, and Wi‐MAX (2.5‐2.7 GHz). 相似文献
14.
In this article a novel wide‐band artificial magnetic conductor (AMC) based wideband directional antenna is presented for ultra‐wideband (UWB) applications. The proposed novel cross‐slot AMC (CSAMC) achieves wide ±90° reflection phase bandwidth of 4.07 GHz (44.69%) and is used as a reflector. The overall antenna structure is designed with 4 × 4 CSAMC unit cell array and has very compact size of (0.584λ0 × 0.584λ0). The proposed structure improves the radiation properties and exhibits 91.5% (3.13‐8.41 GHz) impedance bandwidth (VSWR ≤2). Additionally, it results in significant improvement in gain and front to back ratio. The proposed antenna is fabricated and its measured performance is in good agreement with simulation results. 相似文献
15.
Low‐cost printed circuit board waveguide (PCBWG) technology is employed to develop new waveguide‐fed microstrip antenna arrays with low profile and light weight while maintaining high efficiency and gain at 12.5 GHz. The proposed corporate feed network has two parts: on the antenna layer, microstrip lines are used to form a 2 × 4 sequentially rotated sub‐array of circularly polarized microstrip patches and on the feed layer PCB‐WG is utilized to combine any number of these sub‐arrays to form a larger array. Because PCB‐WGs transmit the power over a large portion of the feed network, losses are substantially reduced and spurious radiations from feed circuit are eliminated. Several microstrip arrays with PCBWG feed were designed and fabricated using standard PCB process. Comparing the results with those of a hybrid array with conventional waveguide feed shows that there is only a negligible degradation in gain and efficiency when bulky and expensive aluminum waveguides are replaced by PCB‐WGs. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009. 相似文献
16.
A novel broadband circularly polarized (CP) C‐shaped slot antenna fed by a coplanar waveguide is presented. The broadband CP operation can be achieved simply using a C‐shaped slot in the ground to produce orthogonal surface currents for left‐hand circular polarization. Using the semicircle‐shaped radiator patch, wide impedance bandwidth and broad axial‐ratio (AR) bandwidth can be obtained simultaneously. The measured results show that the proposed antenna can provide a 10‐dB impedance bandwidth of 105% from 2.78 to 8.92 GHz, and a 3‐dB AR bandwidth of 70.4% from 2.9 to 6.05 GHz. Finally, an antenna prototype with a reflector for unidirectional pattern applications is also developed. The proposed antenna has broader impedance and CP bandwidths but with a more compact size compared with the previous designs. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:739–746, 2015. 相似文献
17.
This article presents a technique to enhance the broadside gain of a CPW fed slot antenna using a single layer metamaterial (MTM) superstrate. A finite array of 3 3 ring unit cell has been designed on both sides of a dielectric substrate to form the MTM superstrate. The gain enhancement is obtained using the zero‐index property of the metamaterial. The broadside gain enhancement for the proposed antenna is 7.4 dB more in comparison to that of the reference slot antenna. The proposed MTM superstrate loaded antenna provides a minimum overall thickness in the context of using ZIM superstrate for gain enhancement of antennas reported in earlier literatures. The overall thickness of the MTM loaded antenna is 0.13λ0, where λ0 is the free‐space wavelength at the resonance frequency of the antenna. Also, a high efficiency of about 93.2% is obtained in this case. The loading of the MTM superstrate produces a minimal effect on the cross polarization performance of the proposed slot antenna. 相似文献
18.
This article presents a systematic design procedure of CPW‐based Composite Right/Left‐Handed Transmission Line (CRLH TL), including the initial design and optimization algorithm. A Graphical User Interface (GUI) is provided to help inexperienced users synthesize CRLH at any given transition frequency, without tedious tuning or iterative trial. An improved fitness function based on Genetic Algorithm (GA) is presented to reduce the return loss and diminish the bandgap. This design procedure is fast and available, and has been verified by both measurement and full‐wave simulation results. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
19.
A flower‐shaped ultra‐wideband fractal antenna is presented. It comprises a fourth iterative flower‐shaped radiator, asymmetrical stub‐loaded feeding line, and coplanar quarter elliptical ground planes. A wide operating band of 12.12 GHz (4.58‐16.7 GHz) for S 11 ≤ ? 10 dB is achieved along with an overall antenna footprint of 15.7 × 11.4 mm2. In addition, other desirable characteristics, that is, omnidirectional radiation patterns, peak gain upto 5 dB, and fidelity factor more than 75% are achieved. A good agreement exists between the simulation and measured results. The obtained results illustrate that this antenna has wide operating range and compact dimensions than available structures. 相似文献
20.
An approximate method for the fast, accurate calculation of mutual admittance between CPW‐fed slots on electrically thin dielectric substrates is outlined. Results for typical broadside slots agree well with that of a full‐wave simulator, confirming that a free‐space homogeneous medium may be assumed to good effect for sufficiently thin substrates. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009. 相似文献