Ground Plane (ground + plane)

Distribution by Scientific Domains


Selected Abstracts


Krylov model order reduction of finite element approximations of electromagnetic devices with frequency-dependent material properties

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5 2007
Hong Wu
Abstract A methodology is presented for the Krylov subspace-based model order reduction of finite element models of electromagnetic structures with material properties and impedance boundary conditions exhibiting arbitrary frequency dependence. The proposed methodology is a generalization of an equation-preserving Krylov model order reduction scheme for methodology for second-order, linear dynamical systems. The emphasis of this paper is on the application of this method to the broadband model order reduction of planar circuits including lossy strips of arbitrary thickness and lossy reference planes. In particular, it is shown that the proposed model order reduction methodology provides for the accurately modelling of the impact of the frequency dependence of the internal impedance per unit length of the thick lossy strip on the electromagnetic response of the stripline structure over a very broad, multi-GHz frequency band, extending all the way down to frequencies in the DC neighbourhood. In addition, the application of the proposed methodology to the broadband modelling of electromagnetic coupling between strips on either side of a lossy ground plane is demonstrated. Copyright 2007 John Wiley & Sons, Ltd. [source]


On the transmission properties of left-handed microstrip lines implemented by complementary split rings resonators

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 2 2006
M. Gil
Abstract In this paper, the transmission properties of left-handed microstrip lines implemented by etching complementary split rings resonators (CSRRs) and capacitive gaps in the ground plane and conductor strip, respectively, are investigated. To this end, we make use of the lumped element equivalent circuit model of the structure, from which an accurate analysis is carried out, and the influence of the main electrical parameters on the transmission properties is pointed out through electrical simulations. Aspects such as bandwidth and in-band ripple control are discussed in detail. The influence of the geometrical parameters is also discussed and interpreted to the light of the equivalent circuit model. From the results obtained, there are inferred design guidelines that are suitable for the design of metamaterial transmission lines subjected to specifications. Copyright 2006 John Wiley & Sons, Ltd. [source]


Sleeve monopole on a circular ground-plane

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5 2003
Zhongxiang Shen
Abstract This paper presents a modal-expansion analysis of a sleeve monopole antenna on a finite ground-plane. Two perfectly conducting plates (one above the monopole and the other under the ground-plane) are introduced to confine the modeling region and to facilitate the modal-expansion analysis. The resulting guided-wave structure is then divided into a number of regions and the electromagnetic field components in each region are expanded into the summation of its modal functions. The surface current distribution on the monopole and the antenna's input impedance and radiation pattern are obtained by finding the expansion coefficients through matching the tangential field components across the regional interfaces. Calculated results by the modal-expansion method agree well with measured results for the return loss of a sleeve monopole fed through a circular ground-plane by a coaxial probe. Numerical results for the surface current distribution, input impedance, and radiation pattern of a sleeve monopole on a circular ground plane are presented and discussed. Copyright 2003 John Wiley & Sons, Ltd. [source]


A bandpass filter with adjustable bandwidth and predictable transmission zeros

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 2 2010
Li Zhu
Abstract In this article, a microstrip bandpass filter with an adjustable bandwidth and predictable transmission zeros is proposed. The proposed filter is implemented by combining two hairpin edge-coupled resonators with interdigital capacitors. Compared to typical edge-coupled filters, the proposed filter provides a wider bandwidth resulting from a higher coupling strength between its resonators. To further increase the coupling and consequently the bandwidth, a pair of etched slots in the ground plane is used. By adjusting the geometrical parameters of the interdigital capacitors and etched slots, the bandwidth can be easily adjusted. The filter features two transmission zeros, which are determined by means of the semi-analytical model developed as part of this work. Furthermore, the proposed filters can be cascaded to obtain a sharper cutoff frequency response. Frequency responses of the filters from measurements are in good agreement with those simulated using IE3D in the 5,9 GHz range. 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. [source]


Analysis and design of passive and active microstrip reflectarrays

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 5 2003
Francesca Venneri
Abstract The design of reflectarrays is a complex and time-consuming process that very often relies on a trial-and-error approach. In this article, a simplified analysis based on a commercial simulator is proposed. This method, valid for both passive and active antennas, uses a simulator to characterize the single radiating cell and evaluates the contribution of the finite ground plane using physical optics approximation. The proposed design technique has been validated by comparing the simulated response of the single element with the experimentally retrieved phase of the active and passive cell. As a proof of the design concept's feasibility, two small reflectarrays, active and passive, have been prototyped and tested. The measured radiation patterns are presented and discussed. 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 370,377, 2003. [source]


Compact dual-band multiple input multiple output antenna with high isolation performance

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2010
Insu Yeom
Abstract A compact dual-band (WLAN 11b; 2.4 GHz , 2.5 GHz, 11a; 5.15 GHz , 5.825 GHz) 2-channel Multiple Input Multiple Output (MIMO) antenna for portable media player (PMP) applications is presented. The proposed antenna is composed of a planar inverted F-shape antenna (PIFA) operating at 2 GHz band and a loop antenna operating at 5-GHz band. The antenna made up of the composite loop and PIFA antenna (CLPA) with connecting line face to the feed point and is orthogonally arranged at the edge of the ground plane for reducing mutual coupling. The antenna shows polarization and pattern diversities with excellent isolation characteristics. The two antennas were connected with each other in the bottom side to improve the isolation at 5-GHz band. The proposed antenna has a sufficient gain in WLAN service band and is compact sized for the PMP applications. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2808,2811, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25614 [source]


Compact top-loaded ultra-wideband biconical antenna for indoor base-station applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2010
W. J. Lu
Abstract A biconical antenna employing the top-loaded technique is proposed for ultra-band (UWB) operation. The antenna is composed of a small cone mounted on a top-loaded disc and a conical ground plane, with both cones electrically connected together using four shorting pins to reduce the lower cutoff frequency. The antenna is investigated using computer simulation and measurement. Results show that the antenna has an impedance bandwidth from 0.8 GHz to over 11.2 GHz, dipole-like omnidirectional radiation pattern, average gain of about 4.2 dBi, and average radiation efficiency of over 88%. The antenna has the advantageous features of compact size, low profile, simple structure, and ultra-wideband characteristic and so is suitable for indoor base-station applications of many existing and future wireless and UWB systems. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2594,2598, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25540 [source]


A compact pentagonal monopole antenna for portable UWB systems

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2010
Paulbert Thomas
Abstract Design of a compact microstrip-fed ultra-wideband antenna suitable for USB dongle and other such space constraint applications is presented. The structure consists of a pentagonal monopole element and a modified ground plane that gives an impedance bandwidth from 2.8 to 12 GHz. Radiation patterns are stable and omni-directional throughout the band with an average gain of 2.84 dBi. The antenna occupies only 11 30 mm2 on FR4 substrate with permittivity 4.4. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2390,2393, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25449 [source]


Size-reduced defected ground microstrip directional coupler

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2010
Ashraf S. Mohra
Abstract In this article, size reduction and harmonic suppression in coupled-lines microstrip directional couplers is attained using dumbbell, and reshaped dumbbell slots, as defected patterns, specifically placed under the metering position in the ground plane. Quantitative investigation of the performance of the directional coupler as controlled by the variations of the DGS rectangular slots height, DGS gap length, and the DGS reshaped rectangular slot height is presented. This concept is further illustrated experimentally for a 12 dB coupler realized on RT/Duroid 5880 substrate. The proposed DGS design confers size reduction because of the shift of the operating frequency to lower values. The measurements are in a good agreement with the simulated results and emphasize the size reduction and the harmonics suppression of the DGS coupled-lines microstrip directional coupler. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1933,1937, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25410 [source]


Effects of parasitic resonance on a vertical transition in multilayer printed circuit boards

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2010
Sung Tae Choi
Abstract This article reports on parasitic resonance effects of a ground plane with/without a ground opening underneath a signal via with an open stub on the performance of a vertical transition in a multilayer printed circuit board. An equivalent circuit model that accounts for the parasitic resonance due to the open stub inductance and the parasitic capacitance is developed and verified with the measured and simulated results. The fabricated transition exhibits a return loss better than about 10 dB and an insertion loss less than 1.9 dB up to 21.5 GHz. A good agreement is observed between measured and simulated results. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 2098,2100, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25404 [source]


Low-cost surface-reduction technique for RFID reader antennas

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2010
Matthieu Egels
Abstract A low-cost technique for surface reduction of patch antennas is presented. It is based on the slow wave phenomenon. To create slow wave, a frequency selective surface has been burned on the ground plane of a patch antenna. With this technique, a patch antenna has been designed. An antenna for RFID reader at 915 MHz has been designed and simulated. It uses a 1.6-mm-thick FR4 epoxy substrate (,r = 4.5 h = 1.6 mm tan (,) = 0.02) measures 61 mm 65 mm. His maximum gain is 2 dB. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1469,1471, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25241 [source]


Small-size printed loop-type antenna integrated with two stacked coupled-fed shorted strip monopoles for eight-band LTE/GSM/UMTS operation in the mobile phone

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2010
Kin-Lu Wong
Abstract A small-size internal printed antenna formed by a loop-type antenna integrated with two stacked coupled-fed shorted strip monopoles is presented. The proposed antenna has a small uniplanar structure of 40 15 mm2 (600 mm2) for eight-band LTE/GSM/UMTS operation in the mobile phone. The loop-type antenna comprises a driven monopole and a coupled portion short-circuited to the system ground plane of the mobile phone; the driven monopole alone contributes a resonant mode for the antenna's upper band, whereas the driven monopole and shorted coupled portion together provide a loop-type resonant path to generate a resonant mode for the antenna's lower band. Two stacked strips are then integrated with the loop-type antenna, with the two strips coupled-fed by the driven monopole and short-circuited to the ground plane through the shorted coupled portion. That is, two stacked coupled-fed shorted strip monopoles are formed and incorporated with the loop-type antenna in an integrated configuration. The two strip monopoles contribute two additional resonant modes to incorporate those generated by the loop-type antenna to achieve the desired wide lower band (698,960 MHz) and upper band (1710,2690 MHz) for eight-band LTE/GSM/UMTS operation. Details of the proposed antenna are presented. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1471,1476, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25257 [source]


L-strip proximity fed shorted rectangular microstrip antenna for mobile communication

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2010
Amit Kumar Singh
Abstract A dual-band L-strip proximity fed shorted rectangular microstrip antenna is proposed and investigated theoretically simulated by HFSS and experimentally. Proposed radiating patch is located about (17.5 mm) above the ground plane. Return Loss and co- and cross polar radiation pattern are presented. Computed and measured results of return loss are in good agreement. The effect of the geometric parameters of the proposed antenna, such as length of the vertical and horizontal portion of the L-strip is also investigated. The impedance bandwidth (,10 dB return loss) 32.5% (calculated) and 33.00% (measured) for the proposed antenna are achieved for optimized antenna design. Significant size reduction (i.e., ,85%) is obtained as compared with conventional rectangular patch of same resonant frequency. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1567,1571, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25235 [source]


A new balance-fed disc-slit monopole antenna for modern wireless systems

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2010
Cheng-Nan Chiu
Abstract This article proposes a novel balance-fed disc-slit monopole antenna for modern wireless systems. The compact antenna is realized by merging a single-ended disc-slit monopole antenna with a defected-ground balun. The resulting antenna has the special merits of high immunity against electromagnetic interference from nearby circuits and less sensitivity to size variation of the corresponding ground plane. A prototype was created and examined, and the results obtained demonstrate the promising performance of the newly proposed antenna. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1239,1240, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25182 [source]


Ultra-wideband coplanar boat microstrip patch with modified ground plane by using electromagnetic band-gap structure for wireless communication

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2010
Dalia N. Elsheakh
Abstract A new antenna structure using triangular patch alongside a small trapezoidal shape ground plane with proximity fed is proposed in this article. The proposed antenna design provides a bandwidth in the range from 2 < 35 GHz with band discontinuities. Improvement is done in antenna performance by using electromagnetic band-gap (EBG) structure. First, dumb-bell shapes as 2D-EBG are etched in the feeding line. Second, embedded spiral artificial magnetic conductor with four arms to introduce sufficient inductive impedance is done. The resultant bandwidth increases to three times than the original bandwidth and reduces the antenna size as well as enhancing the antenna gain. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1159,1164, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25129 [source]


Design of dual-band quadrifilar spiral antennas for satellite-mobile handsets

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2010
R. A. Abd-Alhameed
Abstract A novel quadrifilar spiral antenna is proposed for use in personal communications mobile terminals exploiting the "big low earth orbit" (big-LEO) satellite system (uplink 1.61,1.63 GHz; downlink 2.48,2.5 GHz). Feeding of the antenna from the outer periphery is proposed, to avoid the complexity and space requirements of a centre feed; an externally fed antenna can also be fed either by coaxial cables or stripline. Moreover, the hybrid phasing network and the matching network (if required) can be located outside and possibly printed in the same plane as the antenna structure. Versions of the design were investigated using the method of moments and in hardware realizations. These had a finite ground plane with air dielectric between the spirals and the ground plane. Performance suitable for satellite mobile system applications was demonstrated, including dual-band matching. 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:987,990, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25090 [source]


Rectangle waveguide to substrate integrated waveguide transition and power divider

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 2 2010
Chao Li
Abstract A novel Ku-band transition and power divider between rectangle waveguide (RWG) and substrate integrated waveguide (SIW) is proposed. This transition and power divider is realized by a radiating metal patch located on the backside of a middle dielectric substrate and a coupling aperture etched on the SIW's ground plane. The transition and power divider is studied both simulatively and experimentally. As reported, low insertion loss of not higher than 0.6 dB and good return loss of ,15 dB may be achieved at the frequency range of 12.1,12.8 GHz. The method to increase the bandwidth is investigated. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 375,378, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24902 [source]


Integrated wide,narrow band antenna for multiband applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 2 2010
E. Ebrahimi
Abstract In this article, a novel integration concept is introduced for multiband antennas. An integrated wide,narrow band antenna is presented, which is composed of a shorted microstrip patch integrated to a coplanar waveguide fed ultrawideband monopole antenna. The patch is printed on the reverse side of the substrate using the monopole antenna as a ground plane. A prototype of the antenna is fabricated and verified. This antenna adds the possibility to operate in two of different standards or frequency bands at any given time. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 425,430, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24926 [source]


Simple small-size coupled-fed uniplanar PIFA for multiband clamshell mobile phone application

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2009
Ting-Wei Kang
Abstract In this study, a simple uniplanar printed PIFA occupying a small area of 10 40 mm2 for achieving multiband operation in the clamshell mobile phone is presented. The proposed PIFA is formed by a simple shorted radiating strip coupled-fed by a simple feeding strip and is mounted at the hinge of the clamshell mobile phone; further, the upper ground plane is connected to the main ground plane using an extended connecting strip. With the coupling feed and the connection arrangement between the main and upper ground planes, the proposed PIFA itself is not only an efficient radiator, it can also excite the two ground planes of the clamshell mobile phone as an efficient radiator (dipole-like resonant modes are excited). Thus, with a small occupying area and a simple structure for the proposed PIFA, two wide operating bands at lower and higher frequencies can be provided to cover GSM850/900/1800/1900/UMTS bands for WWAN operation. The antenna also meets the 1-g SAR specification of 1.6 W/kg required for practical applications. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2805,2810, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24756 [source]


Vertically meander-folded, shorted-patch antennas

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2009
Alois Holub
Abstract In this study, a novel miniaturized microstrip patch antenna based on meander-folded, shorted-patch (SP) structure is introduced. The technique enables a decrease of the original quarter-wavelength patch length approximately by the factor 1/N, where N is the number of the vertically placed patch plates above the ground plane. The antenna operational principle is explained with the help of E-field distribution and can be interpreted as SP with vertically meander-folded cavity. Further modification of the top patch plate to ensure symmetrical radiation pattern is proposed. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2938,2942, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24790 [source]


Prediction of radiated EMI from PCB excited by switching noise of IC

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2009
Hyun Ho Park
Abstract This article describes a methodology to predict radiated emission from the printed circuit boards (PCBs) excited by switching noise of integrated circuits (ICs). Radiation characteristics of PCBs were simulated by using commercial 3D full-wave softwares. IC's switching noise was obtained by measurement. The radiated emission can be calculated by these two factors. To verify the calculation, test PCBs composed of power and ground plane were designed and measured in a 3 m semi-anechoic chamber. The calculated radiated emission showed a good agreement with the measured results. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2262,2266, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24603 [source]


Dual-band-rejection filter based on split ring resonator (SRR) and complimentary SRR

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2009
Xin Hu
Abstract A novel concept of a compact, low insertion-loss dual-band-rejection filter (DBRF) is proposed, and its equivalent circuit model is given. The filter consists of single split ring resonators (SRRs) on the top of the host microstrip line and Complimentary SRR etched on the back ground plane. The dimensions of the structure are as small as 1.4 cm 2 cm, while high frequency selectivity is achieved at both band edges due to the presence of two transmission zeros. The filter has an insertion loss of better than 1 dB, a return loss of larger than 10 dB in the passband from 3.3 to 4.0 GHz, and two rejections of greater than 30 dB within 2.5,2.6 and 5.2,5.6 GHz. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2519,2522, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24596 [source]


Frequency selective surface with dual band switchable reflection and transmission characteristics

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2009
A. Munir
Abstract A pin diode-loaded active doubly periodic flat strip FSS is shown to act as a dynamic screen. It is shown that by means of d.c. bias control, we can utilize the screen in, (1) transmission mode as a dual band electromagnetic shutter, or with the inclusion of a ground plane in reflection mode, as (2) a dual band refection canceller, (3) an amplitude shift keying (ASK) spatial modulator. The properties of the FSS are characterized using a specially designed parallel plate waveguide simulator that permits normal incidence excitation of the FSS under test. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2059,2061, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24547 [source]


Composite right/left-handed transmission line based on Koch fractal shape slot in the ground and UWB filter application

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2009
Jian An
Abstract A novel composite right/left-handed transmission line is presented which is synthesized by etching Koch fractal shape slot in the ground plane and series capacitive gap in the conductor strip. Unlike the structures loaded with complementary split ring resonators, the proposed structure can operate at very wideband and is used to design an ultra-wideband (UWB) filter. The UWB filter is fabricated and tested. The relative bandwidth of the ,10 dB return loss is 128% and the insertion loss is larger than ,1.5 dB except at high frequencies. The equivalent circuit model of the proposed structure is presented and the electrical parameters are also extracted. The circuit model results are compared with the simulation and measurement results which verify that not only the extracted parameters are exact but also the equivalent circuit model is reasonable. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2160,2163, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24553 [source]


An internal multiband antenna for WLAN and WWAN applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2009
Chien-Wen Chiu
Abstract In this letter, we propose a novel multiband antenna which can be integrated into a laptop computer for WLAN and WWAN applications. The antenna, evolved from a dual-band inverted-F antenna, is mounted on the top-edge of a vertical ground plane of LCD panel. By adding four parasitic resonators which are short-circuited quarter-wavelength elements, the antenna can achieve wideband performance to cover GSM850/GSM900/DCS/PCS/UMTS and 802.11a/b/g. A simulation was performed by HFSS to optimally design the antenna, and then a practical structure was also fabricated to verify the simulation results. The measured antenna parameters as well as the radiation efficiency are presented to validate the proposed antenna. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1803,1807, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24501 [source]


A wideband aperture-coupled microstrip antenna for S and C bands

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2009
N. Ghassemi
Abstract This article presents a multilayer aperture-coupled microstrip antenna with a nonsymmetric U-shaped feed line. The antenna structure consists of a rectangular patch which is excited through two slots on the ground plane. Experimental results show that the antenna has VSWR < 2 from 2.6 to 6.8 GHz (89%) and the gain of the structure is >7 dB from 2.7 to 4.5 GHz (50%). 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1807,1809, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24500 [source]


Hybrid of monopole and dipole antennas for concurrent 2.4- and 5-GHz WLAN access point

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2009
Jui-Hung Chou
Abstract A novel hybrid of a 2.4-GHz monopole antenna and a 5-GHz dipole antenna is presented to provide concurrent 2.4 and 5 GHz band operation for access-point applications. The two antennas are arranged in a collinear structure and printed on a compact dielectric substrate with dimensions 12 mm 60 mm. The monopole antenna has a meandered radiating strip and is short-circuited to a small ground plane through a shorting strip. The dipole antenna includes two sub-dipoles at the opposite side of a narrow ground plane and fed by a simple T-junction microstrip-line network. The two antennas are closely set with a distance of 1 mm only, yet good port isolation (S21) well below ,20 dB can be obtained. With a low profile, the proposed design can easily fit into the casing of some standard access points and allow the 2.4 and 5 GHz band signals to be simultaneously received or transmitted with no external diplexer required. Good omnidirectional radiation has been observed too. 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1206,1209, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24281 [source]


Wideband cylindrical monopole antenna for multiband wireless applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009
Joong-Chang Chun
Abstract A wideband cylindrical monopole antenna is presented for multiple band applications. Wideband property of the proposed antenna is achieved by the additional resonance from a stepped base part and a convex ground plane. The measured ,10 dB impedance bandwidths are 1.74,3.06 and 5.59,10.62 GHz, which can cover various kinds of wireless services such as PCS (1.75,1.87 GHz), IMT-2000 (1.92,2.17 GHz), WiBro (2.3,2.39 GHz), WLAN (2.412,2.483 GHz, 5.725,5.825 GHz), DMB (2.63,2.655 GHz), and high-band UWB in Korea (7.2,10.2 GHz). 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 15,17, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23981 [source]


Efficient electrically small loop antenna using SRR structure on the ground plane

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009
Joong-Kwan Kim
Abstract In this article, an electrically small loop antenna using capacitive loading is proposed. The loop antenna acts as an inductive element and the gap between two lines of SRR in the ground plane acts as a capacitive element; hence the combined system with these two elements is operated as a LC resonator. The equivalent circuit model of the antenna structure is applied to analyze and qualify the design correctness. Although the proposed antenna has a very small size, it shows a good performance. The measured maximum gain and radiation efficiency of the fabricated antenna at the frequency of 2.04 GHz are 3.6 dBi and 81.02%, respectively. 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 201,204, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24016 [source]


Design of microstrip bandpass and lowpass filters using coupling matrix method and a new hairpin defected ground structure

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2008
Ahmed Boutejdar
Abstract In this work, we present a novel compact hairpin defected ground structure (DGS) bandpass and lowpass microstrip filter using two hairpin-slots etched in the ground plane. A compact microstrip BPF using coupled DGS resonators is designed using coupling matrix method. The designed BPF showed very wide stopband with two transmission zeros. Furthermore, a simple technique to transform the designed BPF to a LPF was presented. The BPF was fabricated and measured. The measurement results showed good agreement with the theoretical and simulation results. 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2898,2901, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23794 [source]