bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ge‐doped microstrutured fiber design by genetic algorithm for directional coupling
Authors: da Silva José Patrocínio 
Published: December 2012

AbstractA new design of a microstructured optical fiber using cylindrical perfectly matched layers is proposed and analyzed through the vectorial beam propagation method (VBPM) in conjunction with genetic algorithm (GA). The fiber is made up from silica doped with germanium and it contains two and three identical horizontals cores surrounded by air holes. First, the signal power launched in the left core is completely transferred to the neighbor core with 100% of the coupling ratio. Next, the signal power launched in the central core is equally divided between the two neighboring cores with 50% of the coupling ratio. Through numerical simulations, it is demonstrated that the optical power can be completely transferred for a propagation distance around 6000 μm to the first application and 4000 μm to the second application. The behavior of the resulting geometry has been optimized by a genetic algorithm in conjunction with an efficient vectorial finite element formulation (GE‐VBPM). © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:281–285, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27308
A low‐voltage varactorless LC‐VCO in 65‐NM CMOS technology
Authors: Lee Hui Dong , Jung Jong Ho , Lee Kwang Chun 
Published: December 2012

AbstractA varactorless LC‐voltage‐controlled oscillator (VCO) topology is proposed.To exploit a frequency tuning, LC‐VCO adopts a variable capacitance block composed with a transistor and a capacitor. The prototype LC‐VCO is implemented in a 65‐nm CMOS technology. The measurement results show a tuning range of 4.31–4.45 GHz and a phase noise of −115.8 dBc/Hz at 1 MHz offset frequency. Power consumption is 2.44 mA from a 0.5 V supply. The die area is only 0.126 mm2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:245–247, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27310
A simple and efficient method to design electromagnetic band gap grids
Authors: Sartori Eduardo Jose , Hernández‐Figueroa H.E. 
Published: December 2012

AbstractThis paper presents a simple design method for behavior of metamaterials of metallic rods. Numerial and experimental results are given. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:421–425, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27311
A dual‐band dual‐element compact MIMO antenna system for mobile 4G terminals
Authors: Sharawi M. S. 
Published: December 2012

AbstractA novel dual‐band four‐shaped printed multiple‐input‐multiple‐output (MIMO) antenna system for long‐term evolution portable terminals is proposed. The low‐frequency band covered is 780–840MHz and the high‐frequency band covered is 2642–2858MHz. The overall size of the printed MIMO antenna system was 50 × 67 × 1.56 mm3. The maximum measured gain for the low and high bands was ∼0 dBi. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:325–329, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27313
Isosceles triangular unequal power divider
Authors: Ray Sudhabindu , Kumar Girish 
Published: December 2012

AbstractA three‐port two‐way isosceles triangular microstrip unequal power divider configuration has been proposed for broadband and direct coupled applications. An isosceles triangular microstrip patch is fed at the vertex of one of its equal angles and unequal power division has been obtained at the other two vertices. Unequal power division from –6.2 to –15.9 dB has been achieved by varying the height of the triangular patch. This configuration has been analyzed using transmission line model and commercially available ie3d software, followed by experimental verifications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:254–258, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27314
Indoor wireless power transfer using asymmetric directly‐strong‐coupling mechanism
Authors: Sun Tianjia , Xie Xiang , Li Guolin , Gu Yingke , Wang Zhihua 
Published: December 2012

AbstractThis letter proposes a new wireless power transfer mechanism named the directly‐strong‐coupling.It adopts only two resonators and it achieves strong‐coupling performances. Asymmetric sizes of antennas are designed to reduce the receiver's size for indoor applications. The mechanism remains a power efficiency of 35.6% over a distance of 1 m. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:250–253, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27315
Design of pentagonal circular fractal antenna with and without notched‐band characteristics
Authors: Kumar Raj , Choubey P.N. 
Published: December 2012

AbstractAn ultrawideband (UWB) pentagonal circular fractal antenna with notched band is proposed in this article. The antenna is excited using CPW‐feed. The notched band from 5.15 to 5.85 GHz is achieved to avoid interference with the WLAN systems using ring resonator slot on feedline. The experimental result exihibits the UWB from 2.5 to 15.0 GHz except the notched band. A parametric study of antenna has been carried out with respect to length and width of the rectangular ring resonator to adjust the notched band and center frequency. The measured radiation pattern of this antenna is omnidirectional in H‐plane and bidirectional in E‐plane. This antenna is useful for UWB communication system, medical imaging, and vehicular radar. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:430–434, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27316
Compact PCB‐embedded GPS antennas loaded with a coupling strip and lumped elements for mobile phones
Authors: Ahn Jungho , Kim Seunghwan , Byun Joonho , Kim Austin S. , Kim Youngsik 
Published: December 2012

AbstractThis article presents compact global positioning system antennas loaded with a coupling strip and lumped elements for mobile phones. The first antenna proposed (Antenna 1) has a one chip capacitor, whereas the second (Antenna 2) uses both a one chip capacitor and an inductor. The size of Antenna 1 is 5 × 10 mm2, whereas Antenna 2 is 5 × 8 mm2. The radiation patterns are almost omni‐directional and the measured peak gain is 0.5 dBi at 1575 MHz. Both antennas are designed and examined via simulation and experiment. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:363–366, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27317
Miniature stubs‐loaded square open‐loop bandpass filter with asymmetrical feeders
Authors: Maharjan Ram Krishna , Kim Nam‐Young 
Published: December 2012

AbstractA miniaturized microstrip stubs‐loaded square open‐loop bandpass filter (BPF) with asymmetrical feeder lines is proposed.Using this filter structure, the improved out‐of‐band rejection characteristics and higher transmission zero can be possible. The filter is based on a combination of electric and magnetic couplings in the central open‐gaps of the square loop resonators. Hence, the combined couplings generate an electromagnetic (EM) flux between the two square open‐loop resonators. The maximum coupling can be obtained by adjusting the open‐loop gap, mounting the two open‐loop resonators spacing, and the orientation of loaded‐stubs inside the loop resonators. The asymmetrical port terminals also help to couple EM energy by maintaining 50 Ω impedance matching with input/output devices. The open‐gap between the two loops of the filter structure strongly prohibit to flow DC current and out band signals. In this article, the presented BPF generates 5.85 GHz resonant frequency. The insertion loss (S21) was measured as −1.6 dB, and the return loss (S11) was −24.8 dB. The simulated predictions are quite agreed with the measurement results. The proposed filter can be implemented in the RFID systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:329–332, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27318
A narrow‐band high‐temperature superconducting filter with wide upper stopband
Authors: Gong Liming , Wei Bin , Cao Bisong , Dong Shiwei , Dong Yazhou , Yu Hongxi , Jun Li 
Published: December 2012

AbstractThis article presents a novel interdigital capacitor resonator (ICR), which has a high spurious frequency and compact size. A six‐pole high‐temperature superconducting (HTS) bandpass filter (BPF) has been designed and fabricated with this ICR on a double‐sided MgO‐based YBCO thin film. Measurement at cryogenic temperature shows a fractional bandwidth of 0.4%, and an ultra high spurious passband at about 4.1 f0. Moreover, the measurement shows a good agreement with simulation in wideband response. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:443–447, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27324
Modified broadband quasi‐Yagi antenna with enhanced gain and bandwidth
Authors: Lee Jong‐Ig , Yeo Junho 
Published: December 2012

AbstractThis article presents a method for improving the gain and bandwidth of a microstrip‐fed broadband planar quasi‐Yagi (QY) antenna.To obtain a better and more stable gain with little variation over a broad frequency band, we used a planar QY antenna with strip‐type elements (a driver dipole and two directors) that had unequal widths and unequal spacing between them. First, to achieve a broad bandwidth of over 50%, a wide strip is used as a nearby director placed very close to the driver dipole. Then, to enhance and stabilize gain over a required frequency band, a narrow strip director and a ground reflector are appended to the driver with a nearby parasitic director. We systematically explain the effect of each element on the input impedance and the realized gain. To validate this proposed design, a QY antenna with a frequency band from 1.75 to 2.7 GHz and a gain of over 5 dBi was designed, then fabricated on an FR4 substrate, and tested. The results show that the fabricated antenna performs well, with a broad bandwidth of 60.4% (1.53–2.85 GHz), a stable gain between 5.38 and 6.41 dBi, and a front‐to‐back ratio of over 10 dB. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:406–409, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27325
Compact composite right‐ and left‐handed bandpass filter with interlocked gap coupling
Authors: Jang Geonho , Kahng Sungtek 
Published: December 2012

AbstractWe propose a novel compact bandpass filter having a mushroom with interlocked gap coupling on FR4 as a composite right‐ and left‐handed structure. The physical size reduction is made possible by the zeroth‐order resonance of the geometry. The stopband suppression >40 dB is obtained by creating transmission zeros implemented with open stubs at ports. The passband has insertion loss < 1.5 dB and return loss < −15 dB at WiMAX‐band. The simulation and measurement validate the design. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:403–405, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27326
Compact microstrip stepped‐impedance resonator (SIR) using localized substrate integrated artificial dielectric (L‐SIAD)
Authors: Wang Xiaoke , Tang Wanchun , Chow Y.Leonard 
Published: December 2012

AbstractThis article presents a stepped‐impedance resonator (SIR) using microstrip line on localized substrate integrated artificial dielectric (L‐SIAD) structure. In L‐SIAD, the metal posts are periodically embedded in the lower substrate right under the microstrip line and connected to the ground plane, which results in the increasing of the effective permittivity and reduction of the SIR size, especially in the length of the SIR. The resonant frequencies of this SIR are analyzed for different post diameter, post height, and post period. Furthermore, the electromagnetic bandgap property due to the periodical posts is also studied, especially the influences on the resonant frequencies of the SIR. In final, this SIR is used to design an ultra‐wideband bandpass filter and the measured results demonstrated that the filter has broad upper stopband, low insertion loss in passband, and compact size. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:371–375, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27327
Compact ultra‐wideband CPW‐fed fan‐shaped antenna with dual band‐notched characteristics using ARC‐shaped slots
Authors: Wang Chen , Yan Ze‐Hong , Li Sheng 
Published: December 2012

AbstractIn this article, a compact coplanar waveguide‐fed fan‐shaped monopole antenna for ultra‐wideband applications with dual band‐notched characteristics is proposed and studied. The antenna with fan‐shaped structure occupies a small size of 35 × 30 mm2. With a pair of arc‐shaped slots introduced on the radiating patch, two frequency‐notched responses at 3.5/5.5 GHz are obtained. The antenna structure is designed, fabricated, and tested. The band‐notched characteristics, VSWR, radiation patterns, gains within the operating band have been observed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:368–371, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27328
Miniaturized frequency selective surface with a bionical structure
Authors: Jiang Wen , Hong Tao , Gong Shu‐xi , Li Cheng‐kai 
Published: December 2012

AbstractA novel miniaturized frequency selective surface (FSS) is proposed.The size reduction is achieved by using the model of leaf arrangement. Compared with conventional cross FSS, the operation frequency of this novel bionic FSS is changed from 10.4 to 4.74 GHz at the same size. Both theoretical and experimental investigations are carried out. It is observed that the miniaturized FSS presents excellent frequency stability with the increase of the incident angle. The proposed FSS can be a candidate for FSS whose miniaturization is required. Method of applying bionics to FSS design will serve as a good candidate for the future FSS design. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:335–337, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27329
DC‐50 GHz RF‐MEMS SPDT switch for high‐reliability applications
Authors: Matabosch Nuria Torres , Coccetti Fabio , Reig Bruno , Deborgies François , Diepppedale Christel , Sibuet Henri , Cazaux Jean Louis 
Published: December 2012

AbstractA large band SPDT (single‐pole double‐throw) switch based on a very advanced RF‐MEMS switch technology for redundancy schemes are presented. This device allowed to reach state‐of‐the‐art working bandwidth (DC‐50 GHz) and RF performances (IL (Insection loss) < 0.8 dB, isolation > 25 dB, and RL > 20 dB). The 200 mm MEMS technology process has demonstrated a very good stability with very low dispersion (deviations < 0.05 dB for the IL and < 0.6 dB for the isolation over the entire wafer and frequency range). An accurate electrical equivalent circuit, modeling the SPDT in the DC‐65 GHz frequency band, has allowed to extract a contact resistance which is as low as 1.4 Ω. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:333–335, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27330
A compact wideband strip antenna for wireless USB dongle application
Authors: Liu Wen‐Chung , Chen Yung‐Lun , Wu Chao‐Ming 
Published: December 2012

AbstractA wideband strip antenna easy for integration with the printed circuit board of a wireless universal serial bus dongle is presented.By simply inserting slots into a rectangular patch, dual resonances with a wide continuous bandwidth of 1.98 GHz (2.9–4.88 GHz) are obtained. The antenna comprising dual‐folded strips and fed by a short microstrip line is simple and has a compact size of only 9.5 × 10 mm2. Prototypes of this design have been constructed and verified to show good agreement between the simulated and measured results. In addition, design evolution of the presented antenna is performed to provide insights into the antenna‐operating mechanism. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:302–304, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27331
Radiofrequency resonance heating near medical devices in magnetic resonance imaging
Authors: Brown James E. , Lee Choon S. 
Published: December 2012

AbstractMagnetic resonance imaging (MRI) is a desirable diagnostic modality because of its excellence soft‐tissue imaging capability. Patients with implanted medical devices are presently denied access to this modality due to adverse interaction of the device with the electromagnetic fields of the MRI system. These adverse interactions include heating near the tissue–electrode interface due to the radiofrequency (RF) field. The purpose of this work is to develop a basic model of the resonance to further explain the mechanism of RF heating in MRI near implanted medical devices. The work will concentrate on simplified structures that can be well understood from an analytical approach. The relationships shown in the simplification can then be extended to the more complex geometry of an implanted lead. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:299–302, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27332
An improved full scanning antenna using left‐handed materials
Authors: Upadhyay Dileep Kumar , Pal Srikanta 
Published: December 2012

AbstractAn improved version of full scanning antenna using left‐handed metamaterial is reported in this article. The antenna profile is designed based on microstrip technology using balanced composite right left handed transmission lines (CRLH TL) approach. Conventional LC network representation of the CRLH TL uses cascaded combination of interdigital capacitor (IDC) in series and vias to the ground plane at the stub ends in shunt, whereas in this article, the design of full scanning antenna using wire‐bonded IDC is reported and its performance is compared with conventional IDC based full scanning antenna. Dispersion diagram of the balanced CRLH TL based dominant mode leaky wave antenna shows the capability of backfire (−90° < θ < 0°) to broadside (θ = 0°) and to endfire (0° < θ < 90°) scanning. Radiation patterns confirm the full scanability of the antenna and it also shows the designed structure has reduced sidelobes in the endfire radiations. Simulated and measured return loss characteristics of the reported antenna structure show an increase in the antenna's operational bandwidth. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:261–265, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27333
Wideband planar microstrip crossover with high power handling capability and low distortion
Authors: Henin Bassem , Abbosh Amin 
Published: December 2012

AbstractThe design of a planar four‐port microstrip crossover is presented. The design starts by using a half‐wavelength square patch and two sets of orthogonal feeding lines. To achieve a wideband performance, four circular slots are introduced in the square patch. A parametric analysis is used to investigate the effect of the utilized slots. Full‐wave simulations and measurements are used to validate the proposed design. The simulated and measured data show less than 1 dB insertion loss, more than 10 dB return loss, more than 19 dB isolation, and about 0.2 ns group delay deviation across the band from 2.1 to 2.75 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:439–443, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27335
Nine‐element frequency independent dielectric resonator array for X‐band applications
Authors: Kumari Runa , Behera Santanu Kumar 
Published: December 2012

AbstractA frequency independent dielectric resonator array (FIDRA) is designed and investigated experimentally for X‐band applications.In this proposed array, nine rectangular shaped dielectric resonators are arranged in log periodic fashion to attain electrical characteristics which will vary insignificantly with frequency over the entire desired bandwidth. The resulted frequency independent array offers up to 56% wider impedance bandwidth with a VSWR less than two. The bandwidth achieved by proposed FIDRA covers a frequency range 6.3–11.2 GHz which is the desired frequency range for X‐band applications in communication engineering. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:400–403, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27337
Aperture‐coupled pentagon shape dielectric resonator antennas providing wideband and multiband performance
Authors: Sharma Satish K. , Brar Manveer K. 
Published: December 2012

AbstractThe aperture‐coupled regular and irregular pentagon‐shaped dielectric resonator antennas (DRAs) are presented providing wideband and multiband performances. The regular and irregular pentagon shape DRAs show wideband impedance matching (S11 = −10 dB) bandwidth of 42% (from 2.55 to 3.9 GHz) and 45.8% (from 2.57 to 4.1 GHz), respectively. Further, the irregular pentagon shape DRA also shows triple bands: 2.42–2.61 GHz (Band 1), 3.15–4.05 GHz (Band 2) and 5–5.65 GHz (Band 3) with a percentage matching bandwidths of 7.55, 23.77, and 12.2%, respectively. These DRAs offer acceptable directional radiation patterns for both wideband and multiband performances. Prototype of the regular pentagon shape DRA has been fabricated and experimentally verified for both the matching bandwidth and radiation performance. The simulated and measured results are in very good agreement. These DRAs can find applications in wireless communications devices such as base stations. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:395–400, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27338
Embodiment of high impedance surface using artificial magnetic conductor with periodically rectangular lattices
Authors: Lee Seungwoo , Kim Nam , Rhee Seungwoo 
Published: December 2012

AbstractWe designed a new transformed symmetrical mushroom‐like surface structure that possesses high impedance surface characteristics by using periodically arrayed artificial magnetic conductors (AMCs) without via holes.The slots that play a key role in the proposed structure were controlled and optimized by simulation for obtaining the desired frequency band. To evaluate the performance, we used the proposed AMC structure as a reflector of λ/4 dipole antenna, whose resulting characteristics were proven that the distance between the antenna and the proposed AMC reflector is about 12 mm at 2.4 GHz, less than one tenth of a wavelength, without deteriorating the antenna performance. The designed reflector has a broader bandwidth (12.6%) and smaller size (0.16 λ) compared to conventional energy band gap (EBG) structures. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:366–368, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27339