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Microstrip Line (microstrip + line)
Selected AbstractsMicrostrip-fed cusp antenna for ultra-wide band communication systemsINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 1 2009Ezzeldin A. Soliman Abstract A novel antenna for ultra-wideband (UWB) applications is presented in this article. The proposed antenna consists of one circular patch placed on one side of a substrate and one circular slot placed on the other side. The antenna is fed with a microstrip line connected to the circular patch. The radii of the circular patch and slot and the separation between their edges represent the three design parameters which are optimized such that the antenna satisfies the design specifications. The proposed antenna has been fabricated using printed circuit board (PCB) technology. It has been characterized both theoretically and experimentally. The measured and calculated results are presented, compared, and discussed. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009. [source] CAD modeling of coplanar waveguide cross-over air-bridgeINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2005Nihad Dib Abstract In this article, a new CAD model for the coplanar waveguide (CPW) cross-over air-bridge is proposed. The model takes into account the CPW open-end capacitance and the vertical strips of the bridge. The section directly underneath the bridge is modeled as a small section of a microstrip line. Our results are in good agreement with the published full-wave results. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005. [source] Analysis and modeling of microstrip-to-coplanar flip chip package interconnectsINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 4 2001Hussein H. M. Ghouz Abstract In this paper, the discontinuity of a flip chip transition between a microstrip line and a coplanar waveguide is investigated and modeled using the finite-difference time-domain method (FDTD) to predict the overall S -parameters of the package. Effects of the bump and via interconnects on the package performance are investigated and discussed. This includes the effects of different staggered transitions and ground connects on the package performance. A reduction of about 10 dB in the bump and via reflections can be achieved by staggering the signal (bump) and the ground connects (bump/via). A staggering distance of about twice the slot width gave minimum reflection over a wide band of frequencies. Moreover, the larger the relative distance between the ground and the center connects the less the reflection due to the discontinuity. Finally, the computed S -parameters of the flip chip package using the FDTD solution are used to develop an equivalent circuit model for the transition discontinuity over a wide frequency band. The equivalent circuit model of the microstrip to coplanar waveguide discontinuity includes more elements and is more complex than other types of transitions. A TEE or PI circuit model has been used to approximate the general circuit model of the discontinuity. Good agreement has been obtained between the S -parameters of the FDTD model and the equivalent circuit models over a wide frequency band. © 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 202,211, 2001. [source] Edge feeding of circular patch microstrip antennasINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 2 2001B. S. Rao Abstract Edge feeding of a circular patch antenna by a microstrip line has been achieved by utilizing the circumferential variation of the field which is fixed by loading the patch. However, loading splits the degenerate modes and gives rise to cross-polarization. Three different techniques are presented to analyze the loaded circular patch antenna. Comparison with the measured results for input impedance and radiation patterns shows good agreement. The concept used here is very general and can be applied to the edge feeding of any ring antenna. © 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 74,85, 2001. [source] A novel miniature monopole tag antenna for passive UHF RFID applicationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2010Hsien-Wen Liu Abstract A novel miniature monopole tag antenna for passive Ultra-High Frequency (UHF) radio frequency identification (RFID) operation is presented. The antenna possesses a two-sided structure that is printed on an FR4 substrate and fed by a 50-, microstrip line. By properly using helical strips and vias, the antenna size can be reduced to a small volume of 10 (L) × 9.5 (W) × 0.8 (H) mm3 to be easily integrated within various portable devices. A miniaturized quasi-lumped circuit is also designed to attain a good impedance matching between the antenna and the chip. Experimental results demonstrate that the antenna has a suitable operating band about 914,939 MHz and also quite omnidirectional radiation pattern with appreciable gain. Moreover, the proposed compact tag antenna, capable of achieving a maximum readable range of about 5.6 m with an EIRP equal to 4 W, is well suited for RFID applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2770,2772, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25596 [source] Compact ultra-wideband bandpass filter using defected ground structuresMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2010J. K. Lee Abstract In this letter, a compact ultra-wideband (UWB) bandpass filter (BPF) is presented with improved upper stopband performance using six defected ground structures (DGS). The proposed BPF is composed of seven DGSs which are positioned under the input and output microstrip line and coupled double step impedance resonator (CDSIR). By using CDSIR and open loop defected ground structure (OLDGS), we can achieve UWB BPF characteristics, and by using the conventional DGSs under input and output microstrip line, we can improve upper stopband performance. Simulated and measured results are found in good agreement with each other, showing a wide passband from 3.4 to 10.9 GHz, minimum insertion loss of 0.61 dB at 7.02 GHz and the group delay variation is less than 0.4 ns in the operating band while wide upper stopband with more than 30 dB attenuation up to 20 GHz. In addition, the proposed UWB BPF has a compact size. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2173,2175, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25436 [source] Adding microstrip line at the bottom of PCB for enhancing antenna bandwidthMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2010B.-G. Cho Abstract In this article, added microstrip line at the bottom area of printed circuit board (PCB) is proposed for improving the bandwidth of GSM900, DCS1800, and PCS1900. By printing the microstrip line at the bottom area of PCB, frequency bandwidth of slim-type cellular phone which has a low-profile monopole antenna is improved. Dimension of the microstrip line is 45 mm × 9 mm. The width and length of the microstrip line is modified for good bandwidth. The measured return loss of the antenna is better than 7.3 dB for low and high band. Measured peak gains of the proposed antenna present 3.41, 5.48, and 5.95 dBi in each band, respectively. Details of the antenna design are described. Its performances are also presented. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1984,1988, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25399 [source] Broadband Wilkinson balun using pure left-handed transmission lineMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2010Young-Ho Ryu Abstract Utilizing the opposite phase shift property of a microstrip line (MSL) and a pure left-handed transmission line (PLH TL), the broadband Wilkinson balun is designed. The PLH TL without a right-handed (RH) branch is designed using effectively negative elements obtained by a cross connection of vias to ground. The PLH TL gives inherently phase-advanced response properties because of negative phase velocity, whereas a conventional MSL has a phase-lag response. The property of a broadband left-handed branch of a PLH TL applies to the implementation of broadband balun. The proposed balun has a good return loss, a good isolation between output ports, an equal-power division, and a 180° ± 10° phase difference in a wide fractional bandwidth of ,71%. Furthermore, the wideband balun that has the fractional bandwidth of 107.8% is theoretically designed with the modified PLH TL having four unit cells. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1665,1668, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25242 [source] Fast and accurate calculation of transmission coefficients for an EBG microstrip structureMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2010Shao Ying Huang Abstract In this article, an approach is proposed to provide an accurate and fast calculation on the transmission coefficients of an electromagnetic band-gap (EBG) structures where patches are periodically inserted into the microstrip line (capacitive loaded EBG microstrip structure). The stopband performance, such as the center frequency, bandwidth, and attenuation, of these EBG structures can be predicted at a high degree of accuracy through the calculation of the transmission coefficient. The dispersion relation of electromagnetic waves in the structure is derived, plotted, and analyzed. The grating nature of the structure is demonstrated. This approach can be applied to periodic microstrip structures of a similar nature to simplify the analysis and design procedures. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:793,797, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25046 [source] Meta-structured one-unit-cell epsilon negative antennaMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2009Seongnam Jang Abstract This Letter presents a metamaterial-based compact one-unit-cell epsilon negative zeroth-order resonant antenna designed on a microstrip line. The size of the proposed antenna is only 7.85 mm × 18 mm (or 0.05,0 × 0.12,0) at 1.79 GHz owing to zeroth-order resonance. Closed-form design equations for the proposed antenna are provided based on the equivalent circuit employing transmission line theory considering radiation loss. The return losses based on circuit/EM simulations and measurement are in excellent agreement. The measured antenna bandwidth is 17 MHz (about 1%) and total gain is 2.6 dBi. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2991,2994, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24751 [source] A dual-band split-ring monopole antenna for WLAN applicationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2009Siddik Cumhur Basaran Abstract In this article, a novel dual-band microstrip monopole antenna based on split-ring elements is proposed for WLAN (2.4/5 GHz) applications. The antenna fed by a two-stage microstrip line has fairly small dimensions and provides 7.5 and 25.5% impedance bandwidth performance at the respective bands. Also, the antenna exhibits almost uniform radiation patterns at each frequency band. The measurement results of the fabricated antenna are in good agreement with the simulations. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2685,2688, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24708 [source] Dual-band-rejection filter based on split ring resonator (SRR) and complimentary SRRMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2009Xin 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] Metamaterial transmission lines with tunable phase and characteristic impedance based on complementary split ring resonatorsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2009Adolfo Vélez Abstract In this article, resonant-type tunable metamaterial transmission lines with independent control over the electrical parameters of the line, that is, the electrical length and characteristic impedance, are presented for the first time. Tuning is achieved by loading a host microstrip line with varactor-loaded complementary split ring resonators (VLCSRRs) and varactor diodes. By locating the varactor diodes in series configuration with the line, outside the region occupied by the VLCSRRs, it is possible to control the characteristic impedance and the electrical length (phase shift), over a wide band. As an illustrative example, a tunable 35 ,/90° line functional between 0.4 and 0.8 GHz (which represents more than 65% tuning range), is presented and applied to the design of a transmission line power divider. The device is small and it exhibits reasonable performance. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1966,1970, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24480 [source] A novel compact ultrawideband (UWB) bandpass filter using multiple-mode resonatorMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2009D. Chen Abstract In this letter, a novel compact ultrawideband (UWB) bandpasss filter (BPF) using the proposed multiple-mode resonator (MMR) is presented. The MMR is composed of a conventional microstrip hairpin resonator of which the two arms are connected by a section of microstrip line and a short-circuited point located in the middle of the hairpin resonator. Its first three resonant modes can be utilized to construct the UWB band. The tapped feeding structure has been used to realize desired tight couplings for designing the UWB BPF. The filter has been investigated numerically and experimentally. Both the simulated and measured results show that the filter has good performance, such as compact size, low-insertion loss, small group delay variation, and improved out-of-band performances. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1662,1664, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24424 [source] Bulk and patch ferrite resonator antennas based on the ceramic matrix composite: GdIGx YIG1- xMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2009P. B. A. Fechine Abstract In this study, the dielectric properties of the GdIGXYIG1,X ferrite composite material at radio frequency (RF) and microwave frequency bands were studied. These measurements were carried out in different sample geometries: thick films and cylindrical ceramic bulk ferrite resonator. In the RF range, we observed that the material is rather stable because of its short changes as a function of temperature and frequency range. The temperature capacitance coefficient values for all the samples (thick films and cylindrical ceramic bulk samples) presented short positive values at the RF range. The GdIG0.5YIG0.5 thick film was used as a substrate for the microstrip antenna device, where the upper Ag electrode served as a circular patch antenna and a microstrip line was used as a feed line. The microstrip antenna operates in this configuration at 8.185 GHz. In the study of the dielectric properties of the composites antenna geometry, with the same ferrite composite, a bulk cylindrical geometry was investigated. A numerical study, together with the experimental, was done, and the dielectric characteristics of the composite like ,r, tg,E, and ,r were obtained. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1595,1602, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24395 [source] Design a new structure 2.4 GHz/5.2 GHz dual-band bandpass filters on the MgTa1.5Nb0.5O6 ceramicMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2009Cheng-Fu Yang Abstract In this article, a ,/2 U-shaped hairpin resonator was contained in a modified end-coupled microstrip line. The increase of the sizes of U-shaped hairpin resonator and modified end-coupled microstrip line had no influence on the lower operating frequency and would shift the upper operating frequency to lower values. After finding the best designed parameters, a miniature dual-band microstrip bandpass filter with three transmission zeros generated in the stop-bands was developed on the MgTa1.5Nb0.5O6 microwave dielectric ceramic substrates. The dual-band filter had the central frequencies of 2.45 and 5.2 GHz and was suitable for the applications in the modern WLAN communication. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1085,1087, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24264 [source] Modeling of shielded broadside-coupled substrate striplinesMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009Sarhan M. Musa Abstract Broadside-coupled substrate striplines represent an essential part of modern integrated circuits. In this article, we will illustrate modeling of inhomogeneous quasi-TEM shielded broadside-coupled substrate striplines using the finite element method (FEM). FEM is especially suitable and effective for the computation of electromagnetic fields in strongly inhomogeneous media. We illustrate that FEM is suitable and effective as other methods for modeling shielded broadside-coupled substrate striplines. We specifically determine the capacitance per unit length, even mode impedance, odd mode impedance, and characteristic impedance of shielded broadside-coupled suspended striplines. Excellent agreement with some results obtained previously is demonstrated. We extended the modeling by designing our own model of shielded broadside-coupled inverted microstrip line and determine the capacitance per unit length, even mode impedance, odd mode impedance, and characteristic impedance. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 9,13, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23960 [source] Synthesis of ultrawideband bandpass filter by multisection of commensurate stepped-impedance resonatorsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2008Chun-Ping Chen Abstract A novel filter prototype composed of multisection of stepped impedance resonators (SIRs) is proposed to realize the ultra-wideband bandpass (UWB) filter. The relation between the modes number and stage number of resonators is first discussed, followed by the derivation of the corresponding Chebyshev filtering function. Furthermore, the equivalent circuit model of this new filter prototype is established based on the transmission-line theory for filter synthesis. As an example, a FCC UWB filter is synthesized with the proposed filter prototype to possess a passband from 3.1 to 10.6 GHz (fractional bandwidth is about 110%). The synthesized circuit model are further optimized by EM simulator, fabricated in microstrip line, and characterized by network analyzer. The good agreement between the measured and predicted frequency responses validates the effectiveness of newly proposed synthesis approach. In addition, the designed filter exhibits good characteristics of comparatively low insertion loss, quite sharp skirts, very flat group delay, and good stopband (especially in lower one) as well. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2635,2639, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23756 [source] Adaptive neuro-fuzzy models for the quasi-static analysis of microstrip lineMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2008Celal Yildiz Abstract This article presents a new method based on adaptive neuro-fuzzy inference system (ANFIS) to calculate the effective permittivities and characteristic impedances of microstrip lines. The ANFIS is a fuzzy inference system (FIS) implemented in the framework of an adaptive fuzzy neural network. It has the advantages of expert knowledge of FISs and learning capability of artificial neural networks. A hybrid learning algorithm, which combines the least square method and the back propagation algorithm, is used to identify the parameters of ANFIS. The results of ANFIS are compared with the results of the experimental works, quasi-static methods, and a commercial electromagnetic simulator IE3D. There is very good agreement among the results of ANFIS models and quasi-static methods, IE3D, and experimental works. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1191,1196, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23322 [source] Microstrip-CPW bandpass filter for antenna applicationMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2008Atallah Balalem Abstract This article presents a quasi-lumped bandpass filter with CPW-microstrip ports. The structure serves as CPW-microstrip transmission in addition to its filtering function. The filter was integrated with a microstrip patch antenna. To enable the filter design, the characteristic impedance of the slotted microstrip line and the coupling strength of microstrip to microstrip, CPW to CPW and microstrip to CPW transitions were calculated. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 51,55, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23001 [source] Lowloss MIC/MMIC compatible microstrip to waveguide transition without a balunMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2008Boro M. Relji Abstract A new MIC/MMIC compatible microstrip to waveguide transition is introduced. Its main feature is balunless design, which assumes direct feeding of waveguide exciter with microstrip line,i.e., without balun. This offer: high-frequency, wideband, and lowloss operation, using lowcost low DK substrates, and size reduction of transition more than three times. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 107,111, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23012 [source] Compact-planar monopole loop antennas for 802.11b/g WLAN systemsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2007Mariusz Bledowski Abstract Two monopole antennas using Koch loop and Minkowski loop radiators fed by microstrip line are proposed for WLAN applications in the 2.45/5.25 bands. To achieve the desired resonances, new configurations of impedance transformer with transmission line length close to ,/12 were designed. The prototypes have been examined, fabricated, and experimentally tested and found to fulfill with excess WLAN system requirements. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2299,2303, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22720 [source] Multiband meander antenna with a backed microstrip lineMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2007Jae H. Kim Abstract A novel multiband meander antenna with a backed microstrip line is proposed for GSM/DCS/ISM and WiMAX triple-band operations. We have used meandering technique and U-shaped line to produce the GSM and DCS bands, respectively, and a backed microstrip line technique to produce the ISM and WiMAX band. Prototypes of the multiband antennas have been successfully implemented and good radiation characteristics in the operating frequency bands have been achieved. The effect of the backed microstrip line geometry on the return loss was also studied. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1942,1946, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22582 [source] Design of triangular slot antenna for triple-band (2.4/5.2/5.8 GHz) antenna with fork-like tuning stubMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2007J. H. Yoon Abstract A novel design for a triangular slot antenna with fork-like tuning stub for 2.4/5.2/5.8 GHz triple-band applications is presented in this article. The prototype consists of a triangular slot and a fork-like tuning stub. The triangular slot is fed by a 50-, microstrip line with a fork-like tuning stub, which is printed on the opposite side of the microwave substrate. As seen in the experimental results, the impedance bandwidth (VSWR 1:2) of the proposed bandwidth is about 550 MHz for the 2.4-GHz band and 1.736 GHz for the 5-GHz band. This is a microstrip antenna for IEEE 802.11a/b wireless local area networks applications. Simulated and experimental results for the return loss, radiation patterns, and gains are presented and discussed.© 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1561,1565, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22499 [source] Dual-frequency antenna for RFID tags with complementary characteristicMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2007Jieh-Sen Kuo Abstract A novel dual-frequency Radio Frequency Identification (RFID) antenna with complementary operation mechanisms (two different operation mechanisms: near field and far field operation) is proposed. The proposed antenna is obtained by printing a rectangular-spiral-shaped and a meander-shaped line, which is placed above on a rectangular microwave substrate as a RFID tag's antenna where its ground plane is at the bottom of substrate. The proposed antenna is fed by a 50 , microstrip line printed on the same substrate, and the antenna's two resonant frequencies can be excited with good impedance matching. Closer to omni-directional radiation patterns and the lower cross-polarization levels (at least 25-dB) are also obtained. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1396,1398, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI.10.1002/mop.22426 [source] Dual-band monopole antenna excited by a capacitive coupling feed for WLAN applicationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2007Chih-Yu Huang Abstract A printed dual-band T-shaped monopole antenna with a shorted strip fed by a coupling microstrip line for wireless communication in the wireless local-area network (WLAN) band is studied. The proposed antenna can provide two separate impedance bandwidths of 101 MHz (about 4.1% centered at 2.45 GHz) and 1490 MHz (about 27% centered at 5.5 GHz), making it easier to cover the required bandwidths for WLAN operation in the 2.45 GHz band (about 3.4% bandwidth required) and 5.2/5.8 GHz bands (about 13% bandwidth required). We can easily find the enhancement of impedance bandwidth by using capacitive coupling feed. Details of the proposed antenna design and experimental results are presented and discussed. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1135,1138, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI.10.1002/mop.22380 [source] Analysis on a novel ultra-wide bandwidth antenna of double-printed circular discMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 2 2007Yi-Min Lu Abstract A novel ultra-wide bandwidth antenna of double-printed circular disc is presented in this article. Some reasonable theoretical analyses are proposed. Printed on the dielectric substrate and fed by a microstrip line, the antenna has been demonstrated to provide an UWB with return loss less than ,10 dB from 3.1 to 10.6 GHz and the satisfactory radiation properties. In addition, an even better impedance matching can be got by improved the feed point, which is quite valuable for broadband antennas design. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 311,313, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22115 [source] New low profile cavity-backed Hilbert slot antennaMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2006Guido Biffi Gentili Abstract In this paper, the use of a cavity-backed Hilbert surface as an efficient slot-like narrowband radiating aperture is suggested, to exploit its own unique electromagnetic characteristics in the context of radio frequency identification (RFID) applications. The proposed meta-slot antenna (MSA) consists of a Hilbert surface window (HSW) made of a cascade of space-filling slot inclusions of order three and backed by a very shallow cavity that contributes to its surface impedance and radiation characteristics. A straight longitudinal microstrip line printed on a thin, low permittivity substrate, whose ground plane includes the HSW, feeds the aperture through distributed electromagnetic coupling. As illustrated by simulation results and measurements, the antenna behaves as a magnetic current sheet over a ground plane, with a highly frequency-selective impedance response and unidirectional radiation pattern. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2577,2581, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21995 [source] The multilayer folded couplers and their applicationMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2006L. Chiu Abstract In this paper, three folded couplers and their application have been presented. The Wilkinson power divider, and 90° and 180° hybrids are folded for size reduction in the multilayered printed circuit media. The folded hybrid ring is employed as the transition between the microstrip line (MSL) and the parallel-strip line (PSL) for balanced circuit applications. The PSL has an inherent advantage of easy realization of balanced configuration, which is suitable for push,pull designs, especially for high power applications. The PSL makes the design of circuits more flexible than MSL because the lump components and solid state devices can be easily mounted in both series and shunt manners without any difficulties in fabrication. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2285,2288, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21913 [source] Design of a new wideband microstrip-fed circular slot antennaMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2006Mohamed A. Habib Abstract In this paper, a new ultra-wideband slot antenna with a simplified feeding network is presented. This antenna is composed of a circular slot coupled to a circular patch fed with 50, microstrip line. A proper parametric investigation was carried out for optimization of the proposed structure. Simulations and measurements show that a large bandwidth from 2.13 to 11.11 GHz can be achieved, which represents a relative bandwidth of 136.4%. Furthermore, good agreement between simulated and experimental results is obtained. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 919,923, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21519 [source] |