共查询到20条相似文献,搜索用时 15 毫秒
1.
Wen-jun Lui Chong-hu Cheng Hong-bo Zhu 《Antennas and Propagation, IEEE Transactions on》2007,55(9):2445-2450
An improved frequency notched ultrawideband (UWB) microstrip slot antenna with a square ring resonator embedded in the tuning stub is proposed. The antenna is investigated numerically and experimentally for its impedance matching property, frequency notched characteristic and radiation performance in detail. As will be reported, compared with conventional frequency notched slot antennas, after incorporating a square ring resonator with the slot antenna's tuning stub, high, sharp band-rejection characteristic of over 20 dB is achieved, which is improved significantly. 相似文献
2.
Printed ring slot antenna for circular polarization 总被引:3,自引:0,他引:3
Kin-Lu Wong Chien-Chin Huang Wen-Shan Chen 《Antennas and Propagation, IEEE Transactions on》2002,50(1):75-77
A new design of a microstrip-line-fed circularly polarized printed ring slot antenna is proposed. Circular polarization (CP) radiation of the proposed design is achieved by introducing proper asymmetry in the ring slot structure and feeding the ring slot using a microstrip line at 45° from the introduced asymmetry. The asymmetry introduced in the proposed design is a meandered-slot section and the proposed CP design can be applied to printed square and annular ring slot antennas. Prototypes of the proposed design have been implemented. Experimental results show that good CP radiation performances are obtained and the 3 dB axial-ratio CP bandwidths obtained for the square and annular ring slot antennas are about 4.3% and 3.5%, respectively 相似文献
3.
A method for miniaturization of microstrip patch antennas without degrading radiation characteristics is investigated. It involves perforating the patch to form a microstrip square-ring antenna, which is investigated numerically and experimentally. The ring geometry introduces additional parameters to the antenna that can be used to control its impedance, resonance frequency, and bandwidth. For a single square ring increasing the size of perforation increases its input impedance, but decreases the resonance frequency and bandwidth. It has a small effect on directivity of the antenna. To match the antenna to a transmission line and also enhance its bandwidth, the ring is stacked by a square patch or another square ring. The computed results are compared with experimental data and again good agreement is obtained 相似文献
4.
Segmentation technique coupled with cavity model have been used to analyze square ring and crossed-strip microstrip patch antennas for circular polarization. This technique is found to predict the characteristics of antennas correctly, as is evident from the close agreement between the calculated and measured results for resonant frequency, input impedance, radiation patterns, and bandwidth. Square ring antenna has been found to have larger impedance bandwidth and axial ratio bandwidth because of lowerQ . Crossed-strip antenna has larger size and thus fabrication tolerances can be relaxed. 相似文献
5.
Jui-Han Lu Chia-Luan Tang Kin-Lu Wong 《Antennas and Propagation, IEEE Transactions on》1999,47(7):1174-1178
Novel designs of single-feed equilateral-triangular microstrip antennas for circular polarization (CP) are proposed and studied experimentally. It is demonstrated that by embedding a narrow slot or a cross slot of unequal slot lengths in the triangular patch, circularly polarized radiation of microstrip antennas can easily be achieved using a single probe feed. Furthermore, results show that for the design with a cross slot, the proposed antenna can perform CP radiation with a reduced antenna size at a given frequency (denoted as compact CP operation here); that is, the required antenna size is smaller for the proposed antenna for performing CP radiation as compared to a conventional circularly polarized triangular microstrip antenna at a fixed operating frequency. Details of the proposed CP designs are described, and typical experimental results are presented and discussed 相似文献
6.
Operating frequencies and radiation patterns of microstrip-fed ring slot antennas are investigated. The microstrip feed is shown to strongly affect the operating frequencies of the slot antenna. As the length of the microstrip stub is increased to exceed half the guided wavelength of the first operating frequency, then multiple operating frequencies with broadside radiation patterns become available. By extending the single microstrip feed to couple to two slot locations, the antenna's operating frequency ratios and polarizations can be tuned. A number of multifrequency microstrip-fed slot ring antennas are demonstrated. Numerical analysis based on the moment method is compared with the experimental results. A dual-frequency antenna array is also reported. 相似文献
7.
A novel frequency-reconfigurable microstrip antenna composed of organic semiconductor polymer (P3HT) is proposed. Resonance frequency of the antenna is tuned in 6.8–7.73 GHz band, by changing the light illumination intensity of a 5 W/cm2 white light source. Behavior of the antenna under different light intensities is investigated and compared to a reference copper antenna. Measured radiation patterns are identical in higher and lower resonant bands. Measured radiation efficiency and gain of the proposed antenna are compared in higher and lower bands. The results indicate that, it is possible to obtain reasonable performance albeit with modest radiation efficiencies. 相似文献
8.
Youngje Sung 《ETRI Journal》2009,31(5):506-509
A novel design of a compact square‐ring slot microstrip antenna for achieving circular polarization (CP) operation is proposed and experimentally studied. By using an arrow‐shaped slot structure as a radiating element, the resonant frequency of the proposed antenna is significantly lowered, which can lead to a large size reduction for fixed frequency operation. The CP radiation characteristics are achieved by loading with proper asymmetry, which can be placed diagonally. A prototype of the proposed design is implemented and its performance is measured. Measured results show that radiation patterns with good CP characteristics are obtained at the resonant frequency. 相似文献
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The design of an aperture-coupled annular-ring microstrip antenna for circular polarization (CP) is presented. The CP radiation of the annular-ring microstrip antenna is achieved by a series microstrip-line-feed configuration through the coupling of a ring slot in the ground plane. The key parameters of the proposed design are investigated using a commercial simulation software based on the Method of Moments to show how to obtain the 50 /spl Omega/ input impedance and optimum axial ratio. The proposed design can be applied to the annular-ring microstrip antennas with different inner radii and substrate thickness, and several antenna prototypes are constructed and measured. Details of the experimental results of the CP performance are presented and discussed. 相似文献
11.
Dual-band circularly-polarized square microstrip antenna 总被引:3,自引:0,他引:3
Kai-Ping Yang Kin-Lu Wong 《Antennas and Propagation, IEEE Transactions on》2001,49(3):377-382
New designs of obtaining dual-band circular polarization (CP) radiation of a single-feed square microstrip antenna are proposed and experimentally studied. The proposed single-feed dual-band CP designs are achieved by inserting four T-shaped slits at the patch edges or four Y-shaped slits at the patch corners of a square microstrip antenna. From experiments conducted, a patch size reduction as large as 36% for the proposed design, compared to a conventional CP design without the inserted slits, has been obtained. Details of the design considerations of the proposed antennas are described, and experimental results of the obtained dual-band CP performances are presented and discussed 相似文献
12.
We-Shyang Chen Chun-Kun Wu Kin-Lu Wong 《Electronics letters》1998,34(11):1045-1047
A novel circular polarisation (CP) design of a single-feed square ring microstrip antenna with truncated corners is described. Experimental results show that the proposed design has a reduced antenna size as compared to the conventional circularly-polarised square microstrip antenna with truncated corners at a given operating frequency. Also, the required size of the truncated corners for CP operation is larger for the present design than for the conventional design using a square microstrip patch, which suggests that the fabrication tolerance is relaxed for the present design. Typical results are presented and analysed 相似文献
13.
A design for dual-frequency microstrip antennas with conical radiation patterns is studied. The dual-frequency operation is achieved by exciting two different resonant modes of the square microstrip patch antenna with four symmetrical shorting walls. Then, a method to enhance the impedance bandwidths of the dual-frequency antenna is proposed, and the experimental results show bandwidths are increased by 19 and 31% at the lower and higher operating frequencies, respectively. Simulation analyses are also performed to support the measured results. 相似文献
14.
The compact microstrip antennas with the dual-band characteristic and reconfigurable qualification have been noticed and investigated in this paper. We have developed the slot microstrip antenna with Sierpinski carpet and Minkowski formations and then the metamaterial loads are placed on this antenna in the slot area. The reflection/transmission method has considered to obtain the permittivity and permeability of the split ring resonator (SRR) as a metamaterial. Finally, we show that by using some junction in the metamaterial layer, we can obtain reconfigurable characteristic. Both antennas have dual-band characteristic where the first antenna has two resonances at 3.2 and 4.5 GHz and in the second antenna by altering the metamaterial layer both resonances are occurring at 3.5 and 5.8 GHz. We show that the antenna has two resonance frequencies that matched with the metamaterial Double Negative (DNG) characteristic. Both antennas are printed on FR-4 also we compared measurement and simulation results together. Aforementioned antennas cover the main wireless, WiMAX and LTE bands with sufficient gain and high efficiency (more than 80% typically) with a bi-directional radiation pattern for the indoor application. Here, the metamaterial is used for controlling the resonances and Sierpinski carpet is developed for matching. 相似文献
15.
《Antennas and Propagation, IEEE Transactions on》2008,56(7):1860-1866
16.
A novel circularly polarised (CP), single-fed microstrip antenna is presented. The antenna consists of a stacked structure of almost square patches. The proposed design has a reduced antenna size compared to the conventional CP microstrip antenna at a given operating frequency. The impedance and axial ratio bandwidths are large and CP radiation quality is excellent over the entire upper hemisphere. The proposed antenna is suitable for global positioning system (GPS) applications. 相似文献
17.
C. F. L. Vasconcelos S. G. Silva M. R. M. L. Albuquerque J. R. S. Oliveira A. G. d’Assunção 《Journal of Infrared, Millimeter and Terahertz Waves》2007,28(10):821-829
This work presents a fullwave analysis for annular ring microstrip antennas on uniaxial anisotropic substrates. The effect of the anisotropic substrates on the antenna performance at the millimeter wave band is investigated. The analysis is performed in the Hankel transform domain using Hertz vector potentials and Galerkin Method. Numerical results are presented for the antenna main characteristics such as resonant frequency and radiation pattern. 相似文献
18.
Aanandan C.K. Mohanan P. Nair K.G. 《Antennas and Propagation, IEEE Transactions on》1990,38(10):1581-1586
A microstrip antenna with large bandwidth is developed using a parasitic technique. Compared to the available wideband antennas, the proposed antenna structure is very compact and gives a less distorted radiation pattern with frequency. An impedance bandwidth eight times that of a conventional patch antenna of the same size is achieved. The concept of coupled microstrip line model is extended for theoretical interpretation of the impedance loci. The experimental procedure and results are described, and a theoretical analysis is presented 相似文献
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本文研究了介质覆盖矩形微带天线的特性,精确的谱域全波分析方法被扩展到这类天线的分析中,给出了理论计算公式,探讨了介质覆盖层和对矩形微带天线的驻波比的影响,实验结果证实了理论计算的正确性。 相似文献