bluuebunny/crossref_metadata_2025_split huggingface dataset:
A tunable dual band notch on a UWB printed slot monopole antenna by using open circuit stubs
Authors: Nezhad Sajad Mohammad Ali , Dadashzadeh Gholamreza , Foudazi Ali 
Published: May 2011

AbstractA new printed wide slot antenna with single‐ and dual‐band notch behavior is presented. The base of antenna is a simple fork‐shaped radiating patch, which covers the ultra‐wideband (UWB) frequency range. By using additional protrudent open circuit stubs on the base patch, multiband notch behavior is obtained. Effects of varying the added stubs parameters on the antenna performance show that the center frequency of band rejections can be finely tuned. The proposed dual‐band notch antenna covers 2.4–10 GHz with two bands rejection for WiMAX (3.3–3.9 GHz) and WLAN (5.7–6 GHz) bands. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26095
Surface‐mount WWAN monopole slot antenna for mobile handset
Authors: Wong Kin‐Lu , Lin Po‐Wei 
Published: May 2011

AbstractA surface‐mount monopole slot antenna with a small volume of 13 × 28.5 × 2.2 mm3 for penta‐band wireless wide area network operation in the mobile handset is presented.The antenna is to be surface‐mounted at a rectangular notch of size 13 × 28.5 mm2 near the bottom edge of the system ground plane. When surface‐mounted, the antenna is closely integrated with surrounding system ground plane on the main circuit board of the handset. The antenna can provide two wide operating bands of 824–960 and 1710–2170 MHz to respectively cover the GSM850/900 and GSM1800/1900/UMTS operations. The surface‐mount antenna mainly comprises a monopole slot of width 4 mm and length 50 mm, which is bent to have a compact size and is fed by a microstrip feedline. Both the monopole slot and microstrip feedline are printed on two opposite surfaces of a dielectric substrate, which is bent into an inverted‐U shape for surface‐mounting on the circuit board of the handset. Details of the proposed antenna are described, and results of the antenna including its specific absorption rate values are presented and discussed. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26096
Design and experimental evaluation of a composite strain rosette using fiber Bragg grating
Authors: Ramos C. A. , de Oliveira R. , Marques A.T. , Frazão O. 
Published: May 2011

AbstractThe purpose of this study is to design a composite strain rosette using embedded fiber Bragg grating (FBG) sensors. Those strain rosettes are meant to be used as alternative to the conventional electric rosettes in structural health monitoring applications being glued at the structure surface. A thin (400 μm) and flexible weaved carbon fiber reinforced plastic (CFRP) composite rosette is proposed. The three FBG sensors were written in a single optical fiber. Special care was devoted to the embedding process of the optical fiber sensors in the weaved composite plate in order to avoid significant alteration of the light reflected back by the FBG. The strain response of the composite rosette was compared to electrical strain gage's when applied at the surface of an aluminium sample submitted to tension, flexion and to dynamic strain. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26098
Bandpass filter with wide stopband using broadside‐coupled microstrip T‐stub/DGS cell
Authors: Luo Xun , Ma Jian‐Guo , Li Erping 
Published: May 2011

AbstractA bandpass filter with wide stopband is proposed using the novel broadside‐coupled microstrip T‐stub/defected ground structure cells in this letter.The resonance of the proposed cell is finely adjusted. Besides, these cells with a proper coupled‐structure (i.e., interdigital coupled scheme) can achieve high selectivity only around the resonance, which leads to wide stopband operation. The measured filter operated at 2.2 GHz (i.e., center frequency f0) exhibits a wide stopband up to 9.1 f0 with a good rejection level greater than 30.5 dB. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26101
Design of printed multistrip monopole antenna for UWB applications
Authors: Shambavi K. , Alex Zachariah C. 
Published: May 2011

AbstractDesign and performance measures of a printed multistrip monopole antenna for ultra‐wideband application are presented. The proposed antenna consists of six quarter wavelength strips of different resonant frequency combined in a manner to provide wide bandwidth and omnidirectional pattern. It operates in the frequency range 2.22∼11.67 GHz with impedance bandwidth (VSWR < 2) of 9.45 GHz and maximum gain of 6.07 dBi. The radiation pattern is nearly omnidirectional in the Azimuthal plane and bidirectional in the elevation plane and the consistency of the radiation pattern exists for almost all frequency in the operating band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26103
Comparative study of slot loaded rectangular microstrip antenna for impedance bandwidth and its verification
Authors: Sameena N. M. , Mulgi S. N. 
Published: May 2011

AbstractThis article presents the comparative study of impedance bandwidth of rectangular microstrip antenna comprising different shaped slots on the patch. It is found that the rectangular slot on the center of patch is effective for the enhancement of impedance bandwidth in comparison with elliptical and circular shaped slots. Further, if the rectangular slot is shifted from the center of the patch, antenna provides dual bands. Later, if the G‐shaped slot is constructed using rectangular slots, antenna gives maximum impedance bandwidth of 78.07% and gain 3 dB. The experimental impedance bandwidth of proposed antennas is verified theoretically. In all the cases, the radiation pattern is found to be broadside in nature. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26105
Bandstop filters with variable upper passbands using embedded line, spurline, and conventional microstrip
Authors: Huse Ching‐Wen , Tsai Yi‐Hsien , Wu Chang‐Yu 
Published: May 2011

AbstractThree planar structures including embedded line, spurline, and conventional microstrip are used to implement bandstop filters and their performances of bandwidth, center frequency and higher‐order stopbands are studied in the discrete‐time domain. A two‐section, equal‐length stub is presented to change the ratio of the next higher‐order harmonic frequency to the fundamental frequency. A filter having upper passband widths of up to nine times the fundamental stopband central frequency can be obtained by using conventional microstrip. A higher‐order bandstop filter is implemented with hybrid embedded line, spurline, and conventional microstrip to show the validity of the design method. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26107
Second iteration fractal Koch planar log periodic antenna design
Authors: Rahim M. K. A. , Karim M. N. A. , Zubir F. , Ayop O. , Samsuri N. A. 
Published: May 2011

AbstractIn this article, the design of log periodic fractal Koch antenna using the second iteration has been developed for ultra high frequency band applications. The ability to reduce the size as maintaining the performances of the antenna such as input return loss and radiation patterns brings fractal Koch and becomes enticing among researchers. The design of the log periodic fractal Koch antenna has been elaborated in this article. The computer simulation technology software has been used to analyze the performances of the designed antenna. This has been compared between simulation and measurement. The results show that this antenna has been reduced by up to 27% in size from the normal log periodic planar dipole antenna. The performance of the antenna has been compared in terms of return losses, bandwidths, and radiation patterns. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26111
Experimental demonstration of a dual‐band electromagnetic band‐gap resonator antenna made out of a simple, single‐layer frequency selective surface
Authors: Ge Yuehe , Esselle Karu P. , Bird Trevor S. 
Published: May 2011

AbstractThe new concept for realizing a dual‐band electromagnetic band‐gap (EBG) resonator antenna using a simple, single‐sided frequency selective surface (FSS) is demonstrated experimentally.The reversal of the gradient of the FSS reflection coefficient phase response, around a FSS resonance frequency, is exploited to achieve two cavity resonance bands in which the FSS behaves as a partially reflective surface (PRS) with an appropriate reflection phase. An FSS, with rectangular slots printed on one surface, is considered for demonstration. The measured performance of a prototype antenna in two bands, around 11.4 GHz and 13.4 GHz, is presented. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26112
A novel printed monopole antenna for future ultra‐wideband communication systems
Authors: Ahmed Osama M. H. , Sebak Abdel‐Razik 
Published: May 2011

AbstractIn this letter, a novel microstrip line‐fed printed monopole antenna for ultra‐wideband (UWB) short‐range wireless communications is proposed. The proposed antenna consists of a trapezoidal‐shaped patch with two elliptical‐shaped cuts from its edge forming a bell‐shaped cut. Experimental results shows that the designed antenna operates over impedance bandwidth 3.2–11.4 GHz for return loss S11 < −10 dB, which almost covering the UWB frequency bandwidth. Moreover, the antenna has a good omnidirectional radiation patterns in the H‐plane with good gain flatness over the frequency range of interest. The antenna transmission characteristics at different receiving angles are also measured. By embedding a simple narrow U‐shaped slot in the radiating microstrip patch, a notch in the frequency band of 5.0–6.0 GHz is obtained. The proposed antenna is considered a good candidate for UWB short‐range wireless communication systems avoiding the interference of the existing wireless systems. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26113
Hierarchical LU decomposition‐based direct method with improved solution for 3D scattering problems in FEM
Authors: Wan Ting , Hu Xiao Qing , Chen Ru Shan 
Published: May 2011

AbstractAn efficient direct method based on hierarchical LU (H‐LU) Decomposition is developed for the solution of large sparse finite element systems.On the basis of hierarchical matrix (H‐matrix) technique, H‐LU direct method provides a data‐sparse way to approximate the LU‐factors of a finite element matrix which are dense originally. The approximate LU‐factors can be computed and stored in the algebra of H‐matrices with logarithmic‐linear complexity. The accuracy of this approximation is controllable related to the different choices of the H‐matrix parameters. A modification algorithm is proposed to efficiently improve the accuracy of the approximate solution computed by the H‐LU‐based direct method. Some numerical examples are provided to illustrate the accuracy and efficiency of the proposed method for finite element analysis of three‐dimensional (3D) electromagnetic scattering problems. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26122
Metamaterials‐inspired miniaturization of UHF patch antennas with circular polarization
Authors: Semouchkina E. , Scholz J. , Perini S. , Semouchkin G. , Lanagan M. , Haupt R. , Simonds H. 
Published: May 2011

AbstractThe area of a ultra high frequency (UHF) patch antenna was reduced 80% by embedding high permittivity plugs in the antenna substrate. It is shown that a nonuniform distribution of plugs provides solutions for such problems of the miniaturized antennas as impedance matching and achieving circular polarization of the signal. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26123
High‐efficiency tapered distributed power amplifier with 2‐μm GaAs HBT process
Authors: Xu Jian , Wang Zhi‐Gong , Zhang Ying , Ma Li 
Published: May 2011

AbstractAn integrated power distributed amplifier, fabricated in a low‐cost 2‐μm GaAs heterojunction bipolar transistor (HBT) technology, is implemented in this letter. A tapered collector line structure combined with the input capacitive coupling technique is used to improve the bandwidth and power efficiency simultaneously. The measurement results give a gain of 8.1dB with a gain flatness of ±0.5dB over a frequency range from 1 to 12 GHz. The output 1‐dB compressing point is 13.9 dBm at 5 GHz and the associated power‐added efficiency is 21.9%. Our work presents very good figure of merit among the recently published distribution amplifiers with different technologies. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26126
An effective impedance matching method for RFID slot tag antennas
Authors: Chen Horng‐Dean , Chu Fu‐Chen 
Published: May 2011

AbstractThis article presents an impedance matching method suitable for various radio frequency identification (RFID) slot tag antennas.By loading a matching slot onto a radiating slot, the impedance of the proposed slot tag antenna can be easily tuned to match the various impedance values of chips by simply changing the length of the matching slot. Two examples of the slot tag antennas are studied. Results show that the designed tags exhibit offer good reading range performances and are excellent candidates for RFID applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26130
Improved band‐notched wideband conical monopole antenna
Authors: Hu Z. H. , Hall P.S. , Kelly J. R. , Gardner P. 
Published: May 2011

AbstractRecently, wideband antennas with band‐notched behavior have attracted increasing interest. This paper presents a conical monopole antenna with four C‐shaped slots to achieve improved band‐rejection behavior with at least 28 dB of gain suppression. Compared to previous work reported in the literature, the antenna provides a relatively wide rejection band with increased gain suppression, at the notch‐band center frequency. The antenna also provides an omnidirectional radiation pattern at frequencies within the operating band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26132
A CMOS 802.15.4a transmitter for sub‐GHz application
Authors: Joo Youngjoong , Kim Hyunseok , Jung Sungyong 
Published: May 2011

AbstractA bi‐phase modulated sub‐GHz ultra‐wideband (UWB) transmitter is designed and tested with standard 0.5‐μm CMOS technology. The maximum power consumption is 2.4 mW, when the pulse repetition frequency is 20 MHz with 420‐MHz center frequency. The proposed sub‐GHz CMOS UWB transmitter complies with IEEE 802.15.4a standard for low data rate wireless personal area network applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26136
Realization of band‐stop filter using deformed omega structure loaded microstrip line
Authors: Kumar G. Arun , Mishra D. , Poddar D. R. , Mishra R. K. 
Published: May 2011

AbstractThis communication proposes a compact microstrip band‐stop filter.It is developed by loading a microstrip line section with deformed omega‐type microstrip. Various loading configurations are considered using electromagnetic simulation. Prototype band‐stop filters were fabricated and measured as well. Well‐matched simulated results and experimental data validate the proposed configuration. A discussion on how different structures affect the stop‐band is given. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26140
Gain improvement of a cavity‐backed slot antenna
Authors: Eldek Abdelnasser A. 
Published: May 2011

AbstractDesign of a high gain cavity backed slot antenna is presented with relatively small size.The large ground plane of the original design is cut 75%. Mushroom cells and ground plane orientations have been employed to improve the antenna gain. An 18.75‐dB maximum gain is obtained with an average gain of 17.3 dB in the entire operating band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26141
Study of bandgap characteristics of 2D magnetoplasma photonic crystal by using M‐FDTD method
Authors: Yang Lixia , Xie Yingtao , Yu Pingping 
Published: May 2011

AbstractTo develop modified finite‐difference time‐domain (M‐FDTD) algorithm with magnetized plasma medium, constitutive equation between current density vector and electric field strength vector is first transformed into s‐domain for decoupling, and then transformed back into time domain so that the FDTD iteration equations can be easily obtained in discrete time domain.Then the reflection coefficients with plasma slab calculated by the proposed M‐FDTD algorithm are compared with analytical to show the validity of our technique. Finally, the M‐FDTD algorithm is applied to calculate the reflection and transmission coefficients of plasma photonic crystal of different plasma parameters. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26143
A study on antenna gain degradation due to digital phase shifter in phased array antennas
Authors: Kamoda Hirokazu , Tsumochi Jun , Kuki Takao , Suginoshita Fumiyasu 
Published: May 2011

AbstractWe studied antenna gain degradation of phased array antennas due to phase quantization by digital phase shifters, where the amplitude weighting for element excitation and the losses in the phase shifters were taken into account. By adding a phase offset to the ideal analog phase shifts before they are quantized, the degradation can be varied as a result of the change in the phase errors due to quantization. It was shown that the amplitude weighting and losses greatly affected the peak‐to‐peak variation of the degradation and they must be taken into account to obtain the optimum phase offset that gives the least degradation in actual phased array antennas using digital phase shifters. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26145
Erratum: Comparison of precorrected FFT/adaptive integral method matching schemes
Authors: Yang Kai , Yilmaz Ali E. 
Published: May 2011

AbstractOriginally published Microwave Opt Technol Lett 53:1368–1372, 2011. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26230 (Original article DOI 10.1002/mop.26006)
Fabric dilatancy and the plasticity modeling of granular media
Authors: Muhunthan B. , Sasiharan N. 
Published: May 2011

SUMMARYA novel conceptual model of the mechanics of sands is developed within an elastic–plastic framework. Central to this model is the realization that volume changes in anisotropic granular materials occur as a result of two fundamentally different mechanisms. The first is purely kinematic, dilative, and is the result of the changes in anisotropic fabric. There is also a second volume change in granular media that occurs as a direct response to changes in stress as in a standard elastic/plastic continuum. The inclusion of the two sources of volume change results in three important datum states. When subjected to isotropic strains, the resulting stress state in granular materials is not isotropic but lies upon the kinematic normal consolidation line. There exists a state at which the fabric‐induced volumetric strain rate becomes equal to the stress‐induced volumetric strain rate making the total plastic volumetric strain rate equal to zero. Granular response changes from contractive to dilative at this phase transformation line. The third datum state is the one in which the stress‐induced volumetric strain rate is zero. The sand, however, continues to dilate at this state with the difference between stress and dilation ratio a constant as predicted by Taylor's stress–dilatancy rule. These predictions are shown in accordance with experimental data from a series of drained tests and undrained on Ottawa sand. Copyright © 2011 John Wiley & Sons, Ltd.
Ectopic Lower Third Permanent Molar within the Mandibular Condyle: An Archaeological Example
Authors: Ponce P. V. , Ogden A. R. 
Published: May 2011

ABSTRACTMigration of mandibular third molars to abnormal anatomic locations is not unknown. Examples reported in the clinical literature are mainly in the ascending ramus of the mandible and the neck of the mandibular condyle, and only four cases have hitherto been reported actually within the mandibular condyle. This case reports on an ectopic lower third molar within the right mandibular condyle in a 19th century male skeleton from Wolverhampton, West Midlands, UK. Examples of this nature have not been found to be described in the bioarchaeological literature; therefore, this case study probably represents the first case reported in this field. Copyright © 2011 John Wiley & Sons, Ltd.
A novel concept for the preparation of alloy nanowires
Authors: Milenkovic Srdjan , Drensler Stefanie , Walter Hassel Achim 
Published: May 2011

AbstractA novel concept for the preparation of alloy nanowires has been developed. By combining two pseudobinary eutectic systems NiAl–W and NiAl–Cr with a completely miscible system Cr–W, a pseudoternary system was created in which there is large two‐phase field between NiAl and W(Cr) solid solutions, separated by a eutectic trough. This enables the fabrication of nanowires with compositions from pure W to pure Cr allowing a free change of the ratio. The directional solidification in the pseudoternary system has been carried out. For the first time alloy nanowires in the W–Cr system have been reported. In addition, nanowires of pure W and Cr were fabricated as well. Moreover, an electrochemical procedure for the release of nanowires from the matrix has been established. magnified image
High yield of W–Cr alloy nanowires with equiatomic composition.
Growth temperature and growth rate dependency on reactor pressure for InN epilayers grown by HPCVD
Authors: Buegler Max , Gamage Sampath , Atalay R. , Wang J. , Senevirathna M. K. I. , Kirste R. , Xu T. , Jamil M. , Ferguson I. , Tweedie J. , Collazo R. , Hoffmann A. , Sitar Z. , Dietz N. 
Published: May 2011

AbstractThis contribution presents results on achievable growth temperatures and growth rates as a function of reactor pressure for the growth of InN by high‐pressure chemical vapour deposition (HPCVD). The InN epilayers were grown at reactor pressures ranging from atmospheric pressure to 19 bar. The results show that the InN growth temperature increased linearly with the reactor pressure from 759 °C to 876 °C. The growth rate decreases from 127 nm/h to 20 nm/h as the reactor pressure is increased from 1 bar to 19 bar. The structural, optical, and electrical properties of the epitaxial layers were analyzed by X‐ray diffraction, Raman spectroscopy, IR reflection spectroscopy, and optical transmission spectroscopy. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)