Bandwidth Of Patch Antenna Research Articles

이동통신용 광대역 패치 안테나 설계

A wideband patch antenna fed by an L-strip feeder is studied. The objective of this paper is to design small wideband antenna for 3G and 4G wireless mobile communication service. The enhanced features were confirmed and proved by comparing the proposed antenna with the antennae that have been reported in the relevant literatures. Measurement results confirm that an impedance bandwidth() of 636MHz(32.5%, fo

60 GHz贴片天线用低温共烧陶瓷基板的微机械加工

To effectively enhance the radiation bandwidth of 60 GHz patch antennas,a micromachining process for the Low Temperature Co-fired Ceramic(LTCC) substrate was proposed.Specific green tape layers of substrate were micromilled to form perforated structures which were then filled with sacrificial materials.Thereafter,the individual layers were stacked up and sintered to form a three-dimensional(3D) microstructure.The cantilevers,enclosing frame structures and embedded microchannels were fabricated to verify the effectiveness of the process.The electrical properties of the antenna designs were validated by a full-wave analysis,and the effectiveness of the cooling channel was experimentally tested.The experiments show that the proposed process solves problems like the variation of contraction rate in various axes and the collapsing of the embedded cavities.The 3D frame,cantilever and the embedded microfluidic structure are fabricated with a maximum aspect ratio as high as 4∶1,and a total thickness of 1.4 mm(14 layers).The cross section size of the microchannel is as large as 200 μm×200 μm and its maximum length is beyond 2.5 cm.With smooth inner walls,the smooth microfluidic flow may provide a cooling effect over 40 K for the integrated power devices with a heating power density of 2 W/cm2.The simulated radiation pattern shows a doubled increase of radiation bandwidth from 2.7 GHz to 5.3 GHz and has a little gain loss.These results demonstrate that simple and low-cost micromachining may effectively enhance the radiation bandwidth of patch antennas without additional costs,which is beneficial to the design and implementation of large scale and highly integrated transmitting/receiving arrays with active power devices.

A SLIM WIDEBAND AND CONFORMAL UHF RFID TAG ANTENNA BASED ON U-SHAPED SLOTS FOR METALLIC OBJECTS

A slim wideband patch antenna designed for the ultra- high frequency (UHF) band radio frequency identiflcation (RFID) tag is presented in this paper, which can be mounted on ∞at or curved metallic surfaces directly. The presented antenna is fabricated on a very thin (only 0.5mm) and low-cost PET substrate (r = 3:8, tan- = 0:02). The proposed design consists of tow coplanar patches radiation unities which are electrically connected to the metallic ground through two symmetrical shorting walls placed at both edge sides of the patches. Double symmetrical U-shaped slots are etched out to improve the antenna bandwidth. A perfect matching between antenna and tag chip can be easily obtained by varying the geometry parameters of the slots. The simulated bandwidth is about 97MHz, which covers the Europe and North America UHF RFID frequency range. The measured maximum reading range of the proposed antenna can be up to 5m when the tag is mounted on a metal plate whose size is 150 £ 150 £ 8mm 3 .

Hybrid Mode Wideband Patch Antenna Loaded With a Planar Metamaterial Unit Cell

A wideband patch antenna loaded with a planar metamaterial unit cell is proposed. The metamaterial unit cell is composed of an interdigital capacitor and a complementary split-ring resonator (CSRR) slot. A dispersion analysis of the metamaterial unit cell reveals that an increase in series capacitance can decrease the half-wavelength resonance frequency, thus reducing the electrical size of the proposed antenna. In addition, circulating current distributions around the CSRR slot with increased interdigital finger length bring about the TM01 mode radiation, while the normal radiation mode is the TM10 mode. Furthermore, the TM01 mode can be combined with the TM10 mode without a pattern distortion. The hybridization of the two modes yields a wideband property (6.8%) and a unique radiation pattern that is comparable with two independent dipole antennas positioned orthogonally. Also, the proposed antenna achieves high efficiency (96%) and reasonable gain (3.85 dBi), even though the electrical size of the antenna is only 0.24λ0×0.24λ0×0.02λ0.

A Reconfigurable Wideband and Multiband Antenna Using Dual-Patch Elements for Compact Wireless Devices

A reconfigurable wideband and multiband C-Slot patch antenna with dual-patch elements is proposed and studied. It occupies a compact volume of 50 × 50 × 1.57 (3925 mm3), including the ground plane. The antenna can operate in two dual-band modes and a wideband mode from 5 to 7 GHz. Two parallel C-Slots on the patch elements are employed to perturb the surface current paths for excitation of the dual-band and the wideband modes. Two switches, implemented using PIN diodes, are placed on the connecting lines of a simple feed network to the patch elements. Dual-band modes are achieved by switching “ON” either one of the two patch elements, while the wideband mode with an impedance bandwidth of 33.52% is obtained by switching “ON” both patch elements. The frequencies in the dual-band modes can be independently controlled using positions and dimensions of the C-Slots without affecting the wideband mode. The advantage of the proposed antenna is that two dual-band operations and one wideband operation can be achieved using the same dimensions. This overcomes the need for increasing the surface area normally incurred when designing wideband patch antennas. Simulation results are validated experimentally through prototypes. The measured radiation patterns and peak gains show stable responses and are in good agreements. Coupling between the two patch elements plays a major role for achieving the wide bandwidth and the effects of mutual coupling between the patch elements are also studied.

A HYBRID METHOD BASED ON DIFFERENTIAL EVOLUTION AND CONTINUOUS ANT COLONY OPTIMIZATION AND ITS APPLICATION ON WIDEBAND ANTENNA DESIGN

An evolutionary learning algorithm based on difierential evolution strategy (DES) and continuous ant colony optimization (CACO) for wideband antenna design is proposed. The advantages of this hybrid method are demonstrated with several mathematical functions and a linear array pattern synthesis. This method is applied to design an E-shaped wideband patch antenna, which achieves the impedance bandwidth 4:8 » 6:53GHz. We compare the hybrid method with the traditional DES and CACO optimization algorithms, and the advantage of this hybrid method over the DES and the CACO is also demonstrated.

A Wideband Circularly Polarized Patch Antenna for 60 GHz Wireless Communications

This paper presents the design of a fully packaged 60 GHz wideband patch antenna incorporating an air cavity and a fused silica superstrate. Circular polarization (CP) is realized by introducing a diagonal slot at the center of the square patch. By optimizing the patch and the slot dimensions, a high efficiency (>90%) microstrip fed CP antenna with an impedance bandwidth of 24% and a 6 dB axial ratio bandwidth of 21.5% is designed. A coplanar waveguide (CPW) to microstrip transition with λ/4-open-ended stubs are then designed to match the antenna to the CPW packaging interface. The experimental results of the final packaged antenna agree reasonably with the simulation results, demonstrating an impedance bandwidth of more than 26% and a 6 dB axial ratio bandwidth of 22.7%.

Wideband Shorted Patch Antenna With a Modified Half U-Slot

A small wideband patch antenna with a modified half U-slot is presented. The antenna has an impedance bandwidth of 40% $({ S}_{11} , which is from 1.72 to 2.58 GHz. The antenna size is electrically and physically small, which is $0.012\lambda_{0}^{2}$ and 240 mm $^{2}$ , respectively. The proposed small antenna has good radiation characteristics, with a peak gain of 2 dBi. The proposed antenna is suitable for small wireless devices with the applications of Wi-Fi, Bluetooth, UMTS, GSM 1800, PCS 1900, and LTE.

Enhancing patch antenna bandwidth by means of uniplanar EBG-AMC

The design of a bandwidth-enhanced uniplanar MPA using EBG-AMC is presented.The designed structure with neither via holes nor multilayer substrates yields bandwidth enhancement still with useful radiation pattern values in its band. Two prototypes, a MPA and a PA with uniplanar EBG-AMC (PA_U-EBG-AMC), are manufactured and characterized based on return losses and radiation pattern. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1372–1377, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25974

Enhanced Gain and Bandwidth of Patch Antenna Using EBG Substrates

Microstrip patch antenna becomes very popular day by day because of its ease of analysis and fabrication, low cost, light weight, easy to feed and their attractive radiation characteristics. Although patch antenna has numerous advantages, it has also some drawbacks such as restricted bandwidth, low gain and a potential decrease in radiation pattern. In recent years, attention to use Electromagnetic Band Gap (EBG) substrates to overcome the limitations of patch antenna. In this paper, we propose a rectangular microstrip patch antenna with EBG substrates and compare the performance of the proposed antenna with a conventional patch antenna in the same physical dimension. Due to the presence of the EBG structure in the dielectric substrates, the electromagnetic band gap is created that reduces the surface waves considerably. As a result, the performance of the proposed antenna is better comparing the conventional existing microstrip patch antenna.

Frequency-Tunable High-Power Mesoband Microwave Radiator

This paper presents a frequency-tunable high-power mesoband microwave radiator that uses a switched quarter-wavelength oscillator and a patch antenna. The oscillator is charged and then switched by an annular electrode between the inner and outer conductors. The length of the oscillator is adjustable by moving the electrode in order to generate different frequency resonances. A coupler with a quasi-constant coupling coefficient was employed to output a high-power mesoband microwave. A novel high-power wideband patch antenna with a bandwidth of 64% and a maximum gain of 8.1 dB was used to radiate the generated mesoband microwave. The experimental results of the radiation factor were as high as 182 kV at 333 MHz, and the measured center frequency of the radiated mesoband microwaves ranged from 227 to 345 MHz.

Compact Expressions for Efficiency and Bandwidth of Patch Antennas Over Lossy Magneto-Dielectric Materials

Closed-form formulas for calculating the radiation efficiency and bandwidth of patch antennas over lossy magneto-dielectric materials are proposed by using the cavity model. These expressions agree well with simulations. It is well known that the bandwidth of microstrip antennas is enhanced when the dielectric substrate is replaced by a magnetic one. Here, we confirm more generally that not only the bandwidth, but also the radiation efficiency, can be improved when the permeability (μr) is greater than the permittivity (er).

Compact Broadband Crescent Moon-Shape Patch-Pair Antenna

A novel compact wideband patch antenna is presented. The antenna consists of two simple patch pairs with opposite phase feed. Considering the coupling between two patches in the design, an antenna with a size about 54.5 × 22 × 20 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> is constructed and tested. The simulated and measured results show that the antenna has the active reflection coefficient less than -9.6 dB in the band 2.6-6 GHz. The radiation performance of the antenna is good over the whole frequency band.

Wideband RFID Tag Antenna for Metallic Surfaces Using Proximity-Coupled Feed

A low-cost, wideband patch antenna for radio frequency identification tags mountable on metallic surfaces is presented. A novel proximity-coupled feed structure, in which the direction of the microstrip feed line is parallel to that of the resonant length of the radiating patch and one end of the feed line is shorted to the ground, is proposed to perform simple and wideband impedance matching between the antenna and tag chip without any additional matching networks. The proposed design is verified by simulation and measurement. The measured 3-dB return-loss bandwidth is about 49 MHz, which totally covers the 26-MHz bandwidth requirement in North America. The measured read range is about 8.9 m when the tag antenna is mounted on a metal plate with a size of 200 × 200 mm2.

Wideband dual-layer patch antenna fed by a modified L-strip

A wideband patch antenna is proposed. By using the dual-layer patch configuration and modified L-strip feed technique, the impedance bandwidth of the patch antenna for VSWR<1.2 is broadened to 22% with respect to 900 MHz, which is superior to the other available patch antennas. In addition, by means of the modified L-shaped strip, the high cross polarization levels of the proposed antenna are suppressed effectively. Simulation results are compared with the measurements, and a good agreement is obtained. The measurements show that the antenna has a low cross-polarization level (<-20dB) and an acceptable gain level (~9dBi) across the operating bandwidth. At last, a parametric study and a design guideline of the proposed antenna are also presented to facilitate the design and optimization processes for engineers.

Optimization of E-shaped patch antenna

Bandwidth, size and polarization optimizations of a single layer wide-band full and half E-shaped patch antenna fed through a coaxial probe are described. The finite-difference time-domain (FDTD) method was used in the simulations. Measurements and simulations using capacitive feeding and shorting pins are presented. Using these techniques, the bandwidth can be improved up to 32% and the antenna area can be reduced up to 60% without significant change in the frequency band. Using four raised conducting walls on edges of the ground plane, the cross-polarization level is improved. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1556–1561, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25227

Bandwidth Limitations on Linearly Polarized Microstrip Antennas

The Bode-Fano integral can be used as an objective tool for assessing the bandwidth of antennas, and especially schemes for bandwidth improvement. Results for U-slot and E-slot dual resonant patch antennas suggest that the Fano integral is invariantly related to the overall volume. The Bode-Fano and Youla theories of broadband matching have been applied to the narrowband and wideband lumped equivalent circuit of microstrip antennas to calculate the maximum achievable return loss-bandwidth product of linearly polarized microstrip antennas. Curves are presented showing the relation between the antenna bandwidth, maximum achievable return loss, and parameters of the equivalent circuit. It has been shown that creating parallel slots on the patch despite all potential advantages, may reduce the potential bandwidth of patch antennas.

Particle swarm optimization of L‐probe fed E‐shaped patch antenna using single‐objective function

AbstractAn application of particle swarm optimization (PSO) for wideband patch antenna design is presented in this article. A PSO kernel is built on a MATLAB‐driven MoM‐based EM simulator FEKO. The chosen antenna geometry in this study is the E‐shaped patch but excited by an L‐probe feed. Ten geometrical parameters are optimized simultaneously with the use of a single‐objective: impedance bandwidth broadening. The desired center frequency of this ceiling mounted WLAN (IEEE 802.11a/n) antenna is set at 5.5 GHz with butterfly beam operation. E‐shaped patch geometry of higher order mode is obtained from the PSO‐EM optimizer. The simulated results are verified by the experimental results that a ∼3.5 dBi gain at the elevation angles of ±36° and a &gt;50% of 10‐dB return‐loss bandwidth are obtained at the price of high cross‐polarization levels. This suggests that a multiobjective particle swarm optimization should be used for the wideband antenna design in the future study. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 702–706, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25016

Design of LTCC Wideband Patch Antenna for LMDS Band Applications

This letter presents a wideband patch antenna on a low-temperature cofired ceramic substrate for Local Multipoint Distribution Service band applications. Conventional rectangular patch antennas have a narrow bandwidth. The proposed via-wall structure enhances the electric field coupling between the stacked patches to achieve wideband characteristics. We designed same-side and opposite-side feeding configurations and report on the fabrication of an experimental 28-GHz antenna used to validate the design concept. Measurements correlate well with the simulation results, achieving a 10-dB impedance bandwidth of 25.4% (23.4-30.2 GHz).

宽带高功率贴片天线优化设计与实验

宽带高功率贴片天线优化设计与实验