bluuebunny/crossref_metadata_2025_split huggingface dataset:
Compact cavity‐backed four‐arm slot spiral antenna
Authors: Chen Min‐Hua , Zhong Shun‐Shi , Xu Sai‐Qing , Li Li‐Xian 
Published: June 2009

AbstractThis article introduces a miniaturized four‐arm slot spiral antenna on a ceramic dielectric substrate with a thin back cavity. The simulated and experimental results show that the proposed antenna is of good circular polarization and radiation pattern properties at 1.561 GHz, with measured gain of more than 6 dB at the zenith, and more than −4 dB for above 5° elevation angle. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2141–2143, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24534
Dark‐bright optical solitons conversion via an optical add/drop filter
Authors: Mitatha S. , Chaiyasoonthorn N. , Yupapin P. P. 
Published: June 2009

AbstractWe propose a new system of the dark‐bright solitons conversion using a micro and nano ring resonators incorporating an optical add/drop filter, where the add/drop filter can be used to convert the dark soliton to bright soliton. The key advantage of the system is that the detection of the dark soliton pulse is normally difficult due to the low level of the input power. Firstly, a dark soliton pulse is input into a micro ring resonator then propagating into a smaller micro and nano ring resonators, respectively. Secondly, the add/drop filter is applied (connected) into the ring system, where the bright and dark solitons are obtained via the drop and through (or throughput) ports of the add/drop filter, respectively. Results obtained have shown that the detected soliton power can be controlled by the input soliton power and the ring resonator coupling coefficient, which is enough to use in the transmission link. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2104–2107, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24537
Inward transform method for predicting the field in the inner area between the source antenna and the antenna under test
Authors: Oh Soon‐Soo , Moon Jung‐Ick , Jung Young‐Bae 
Published: June 2009

AbstractIn this article, we propose a new method for predicting the electromagnetic field in the inner area between the source antenna and the antenna under test, utilizing a far‐field measurement system. In particular, we describe the selection of the optimum number of data to be measured, as this is critical to the accuracy. The fields are measured and then transformed into the field in the inner area. The accuracy was verified by simulation and experiment. This inward transform method can be used for determining the worker safety area against high‐power microwave systems. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2032–2034, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24541
Performance of the Volterra behavioral model for wideband amplifiers
Authors: Crespo‐Cadenas Carlos , Reina‐Tosina Javier , Madero‐Ayora María J. 
Published: June 2009

AbstractIn this article, we test the performance of a Volterra behavioral model for wideband amplifiers, which has been theoretically developed based on the frequency dependence knowledge of the nonlinear transfer functions. Relying on a simple measurement setup, a commercial driver amplifier has been extensively characterized at 915 MHz and modeled by using a WCDMA‐like probing signal at different power levels. The calculated values of the normalized mean square error (NMSE) versus the model memory length were compared with a standard memory polynomial (MP) model. To assess the accuracy of the model with other modulation formats, parameters extracted with the WCDMA‐like signal were used to predict the response for a 2‐MHz‐wide GSM‐like signal. For each memory length, the NMSE was calculated again and compared with the corresponding MP model. In all tested cases, results show that the proposed model exhibits a better performance even in the range of memory lengths, where both the models have a very similar number of coefficients. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2166–2169, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24542
Fabrication of a polymer CPW electro‐optic modulator using a strip‐loaded waveguide structure
Authors: Gao Weinan , Sun Jie , Sun Xiaoqiang , Yan Yunfei , Gao Lei , Zhang Daming 
Published: June 2009

AbstractIn this letter, the successful demonstration of a coplanar waveguide (CPW) Mach‐Zehnder (MZ) electro‐optic (EO) modulator using a strip waveguide structure is described and fabricated. The EO active hybrid material is synthesized by sol–gel process. A large EO coefficient of r33 = 50 pm/V with a long‐term stability at 80°C for 200 h was gained. It also has a controllable refractive index and permits a high‐loading concentration. A simple and easily fabricated strip‐loaded waveguide structure is designed and demonstrated to utilize the EO material, which is suitable to reduce the coupling loss with optical fiber. The measured half wave voltage (Vπ) of the CPW MZ modulator is about 8.5 V at 1550 nm in a 3.5‐cm‐long sample. The optimized design principles of the efficient transmission for such a modulator are also discussed in this letter. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2097–2100, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24546
DVB‐H antenna structure using Z‐type hexagonal ferrite for folder‐type mobile phones
Authors: Rhyu Hanphil , Jung Chang Won , Lee Byungje 
Published: June 2009

AbstractA new internal antenna structure using a Z‐type hexagonal ferrite is introduced for the DVB‐H reception in folder‐type mobile phones. The antenna element operates as a coupling element to excite the chassis as a radiator. Using a Z‐type hexagonal ferrite, the proposed antenna can be designed with a considerably low volume of 0.75 cm3 and meets the requirements of antenna for the DVB‐H service. The high isolation over 15 dB between the DVB‐H band and the communication bands (GSM, DCS, and PCS) is obtained. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2196–2199, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24551
Efficiency measurement of UWB and UHF antennas in small cavities of arbitrary shape
Authors: Pintos Jean‐François , Guivarch Sylvain , Louzir Ali , Lemoine Christophe , Le Fur Gwenn , Besnier Philippe , Sharaiha Ala 
Published: June 2009

AbstractA new method that extends the application of spherical Wheeler cap to relatively small cavities of any shape is presented for radiation efficiency estimation. We introduce a modified Huynh formulation to take into account cavity losses when they are non‐negligible for high frequencies. These assumptions are consistent with experimental results, which are based on antenna measurements in cubic cavities and for different frequency bands. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2193–2196, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24552
Composite right/left‐handed transmission line based on Koch fractal shape slot in the ground and UWB filter application
Authors: An Jian , Wang Guang‐Ming , Zeng Wei‐Dong , Ma Lai‐Xuan 
Published: June 2009

AbstractA 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
A feed forward method for stabilizing the gain and output power of an erbium‐doped fiber amplifier
Authors: Vijayakumar N. , Sreeja R. 
Published: June 2009

AbstractThe gain and the output power of an erbium‐doped fiber amplifier (EDFA) are found to be sensitive to input power level fluctuations. Many feed back methods have been proposed to stabilize the gain of an EDFA. These feed back methods are based on sampling and detecting output light and using it to control the pump laser. Such methods fail when the amplifier is expected to repeat a multi‐gigabit data stream. It then becomes necessary to use all more complex optical feed back methods to stabilize the gain. In this article, we propose a novel feed forward technique for stabilizing the output power or gain of an EDFA. A lithium niobate (LiNbO3)‐based Mach–Zehnder interferometer is used to modulate the intensity of pump light in accordance with the input signal level so as to retain constant output power or gain. We observe that the gain or output power of EDFA can be stabilized by proper selection of the parameters of EDFA and modulator. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2156–2160, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24554
An ultra‐wideband bandpass filter having sharp skirt property and large attenuations in its stopband
Authors: Watanabe Koji , Ma Zhewang , Chen Chun‐Ping , Anada Tetsuo 
Published: June 2009

AbstractAn ultra‐wideband (UWB) bandpass filter having a midband frequency of 4.1 GHz and a fractional bandwidth of 34.1% is developed to meet Japan's UWB low‐band spectrum limit. To get sharp skirt property near the passband and large attenuations over a wide stopband, a microstrip stub‐loaded ring resonator and parallel‐coupled stepped‐impedance two‐mode resonators are used simultaneously, and their advantages are fully exploited. Both the simulated and measured frequency responses of the filter satisfy well Japan's low‐band spectrum limit. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2093–2097, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24557
Compact dual‐mode microstrip bandpass filter with adjustable transmission zero
Authors: Zhang Juan , Li Guo‐Hui , Wang Zhi‐Bin , Wang Hui‐Na 
Published: June 2009

AbstractA novel compact dual‐mode microstrip bandpass filter (BPF) with adjustable transmission zero (TZ) is proposed. It is composed of a nested microstrip square‐loop resonator. The filter with two TZs in the lower and upper stopbands is designed, fabricated, and measured. A circuitry size reduction of 55% is achieved by the proposed filter when compared with the convention dual‐mode filters with nonorthogonal feed lines. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2049–2051, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24560
A neural network‐based approach to determine FDTD eigenfunctions in quantum devices
Authors: Soriano Antonio , Segura Jaume , Dima Gh. Tudor , Navarro Enrique A. 
Published: June 2009

AbstractThis article combines a Neural Network (NN) algorithm with the Finite Difference Time Domain (FDTD) technique to estimate the eigenfunctions in quantum devices. A NN based on the Least Mean Squares (LMS) algorithm is combined with the FDTD technique to provide a first approach to the confined states in quantum wires. The proposed technique is in good agreement with analytical results and is more efficient than FDTD combined with the Fourier Transform. This technique is used to calculate a numerical approximation to the eigenfunctions associated to quantum wire potentials. The performance and convergence of the proposed technique are also presented in this article. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2017–2022, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24562
Planar multilateral monopole antenna with band‐notch characterization for UWB applications
Authors: Wang Xiao‐Ming , Weng Zi‐Bin , Zhang Xin , Jiao Yong‐Chang 
Published: June 2009

AbstractIn this article, a novel CPW‐fed band‐notched UWB antenna is proposed. The prototype consists of planar multilateral disc monopole and ground plane. By inserting a symmetry rhombus‐shaped thin slot on the radiation element and square slots on the ground, the narrow frequency band notch has been created to cover the desired frequency varying from 3.4 to 3.69 GHz and the required UWB bandwidth is also acquainted. Also, good radiation patterns and gains within the operating band have been observed. The detailed design and experimental results are discussed in this article. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2186–2189, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24564
Novel doubly perforated broadband microstrip branch‐line couplers
Authors: Kurgan P. , Kitliński M. 
Published: June 2009

AbstractTwo broadband compact doubly perforated hybrid couplers have been designed, manufactured, and measured. To improve frequency characteristics and to reduce circuit dimensions, two kinds of perforations have been introduced: the defected ground structures in the ground plane metallization and photonic bandgap cells in the strip metallization. Measurement results show essential miniaturization (∼39% and ∼36%) and enhancement of the bandwidth (∼47% and ∼75 %). © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2149–2152, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24566
Compact ultra‐wide band microwave filter utilizing quarter‐wave length short‐circuited stubs with reduced number of vias
Authors: Razalli Mohammad Shahrazel , Ismail Alyani , Adzir Mahdi Mohd , Hamidon Mohd Nizar 
Published: June 2009

AbstractWe present here a novel pattern with compact size of ultra‐wide band microstrip filter. The filter is originally modeled from five poles quarter‐wavelength short‐circuited stubs. It is then, transformed into a new compact butterfly‐like pattern. This new “butterfly‐shaped” pattern consists of three vias instead of five vias from its original design. The prototype has shown an improvement in scattering parameters measurement compared with its original model. It delivers 112% of fractional bandwidth, magnitude of insertion loss better than 1.6 dB and return loss lower than −8 dB. It is fabricated on RT Duroid 5880 with 2.2 dielectric constant, 0.508 mm of substrate thickness and 35 μm copper thickness. The overall dimension of the filter is 20.7 × 15.8 mm2. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2116–2119, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24568
Ultrawideband printed patch antenna in notch
Authors: Lin Shun‐Yun , Ke Bi‐Jin 
Published: June 2009

AbstractThis article firstly introduces a compact printed patch antenna with ultrawide bandwidth. The performance is achieved by placing the radiating patch above a rectangular notch cut in the finite ground plane edge. This fabrication provides an ultrawide impedance bandwidth and reduced antenna dimension by suitable separations of the patch from the notch edges. A practical design and experimental results for the requirement of WiMax 802.16e are presented. Moreover, using the proposed antenna as the complementary elements, a dual‐polarization ultrawideband antenna design is implemented and studied. The experimental results indicate that not only the original characteristics are preserved from the dual‐polarized integration but also a larger than 25‐dB isolation is achieved throughout the operating band. In addition, omni‐directional radiations in the azimuthal plane are achieved to make the proposed dual‐polarization antenna more suitable for mobile communications. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2080–2084, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24570
Directive emission based on a new type of metamaterial
Authors: Zhu Fang‐Ming , Wang Zhi‐Yu , Jiang Tao , Shen Lin‐Fang , Ran Li‐Xin 
Published: June 2009

AbstractIn this article, the highly directive emission based on a new type of metamaterial has been demonstrated. A structure of crossed metallic strips with slots is designed. By embedding the source inside a slab of such material, the emitted energy is concentrated around the normal of the slab based on the zero refraction principle. An antenna is constructed, and the simulation has been done on it. The results show that highly directive property is achieved. An experimental verification of this effect is given in the microwave domain, and the results agree well with the simulations. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2178–2180, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24576
Design of CPW‐fed cavity‐backed slot antennas operating at 30 GHz
Authors: Guo Jian , Xu Zhengbin , Qian Cheng , Dou Wenbin 
Published: June 2009

AbstractThis article describes a cavity‐backed slot antenna fed by a coplanar waveguide (CPW). The designed antenna operates at 30 GHz and uses an inverted configuration with the CPW feed line on the top of the substrate and the slot facing toward the metallic cavity. Both simulated and measured results for the antenna's return loss and radiation patterns are presented and they are in good agreement. This slot antenna of a very compact size and good radiation characteristics should be very useful for many communication systems at 8 mm band. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2143–2145, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24578
Harmonic suppressed and size‐reduced bandstop and bandpass filters
Authors: Alkanhal Majeed A. S. , Mohra Ashraf S. 
Published: June 2009

AbstractNew bandstop/bandpass microstrip structures with harmonic suppression are presented in this article. By replacing the series quarter‐wavelength connecting lines of conventional open‐stub bandpass/bandstop filters with the equivalent Π‐shaped line section, compact open‐stub bandstop/bandpass filters with second harmonic suppression are achieved. Transmission‐line theory is used to derive the design equations of the equivalent Π‐shaped lines. Simulation and experiments have also been done to validate the proposed design concept. When compared with the conventional open‐stub Bandpass/Bandstop filters, the second harmonic is suppressed and size reduction is achieved in both the Bandstop/bandpass structures. Moreover, results confirm that the proposed shaped bandpass filter achieves a further third harmonic rejection. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2109–2114, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24580
Erratum: Tunable bandstop filter‐based defected ground structure using a metal plate
Authors: Sung Youngje 
Published: June 2009

AbstractOriginally published Microwave Opt Tech Lett 51:160–163, 2009 © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2254–2255, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24589
Numerical modeling of creep and creep damage in thin plates of arbitrary shape from materials with different behavior in tension and compression under plane stress conditions
Authors: Zolochevsky A. , Sklepus S. , Hyde T. H. , Becker A. A. , Peravali S. 
Published: June 2009

AbstractA constitutive model for describing the creep and creep damage in initially isotropic materials with characteristics dependent on the loading type, such as tension, compression and shear, has been applied to the numerical modeling of creep deformation and creep damage growth in thin plates under plane stress conditions. The variational approach of establishing the basic equations of the plane stress problem under consideration has been introduced. For the solution of two‐dimensional creep problems, the fourth‐order Runge–Kutta–Merson's method of time integration, combined with the Ritz method and R‐functions theory, has been used. Numerical solutions to various problems have been obtained, and the processes of creep deformation and creep damage growth in thin plates of arbitrary shape have been investigated. The influence of tension–compression asymmetry on the stress–strain state and damage evolution, with time, in thin plates of arbitrary shape, has been discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Bi‐criteria optimal control of redundant robot manipulators using LVI‐based primal‐dual neural network
Authors: Cai Binghuang , Zhang Yunong 
Published: June 2009

AbstractIn this paper, a bi‐criteria weighting scheme is proposed for the optimal motion control of redundant robot manipulators. To diminish the discontinuity phenomenon of pure infinity‐norm velocity minimization (INVM) scheme, the proposed bi‐criteria redundancy‐resolution scheme combines the minimum kinetic energy scheme and the INVM scheme via a weighting factor. Joint physical limits such as joint limits and joint‐velocity limits could also be incorporated simultaneously into the scheme formulation. The optimal kinematic control scheme can be reformulated finally as a quadratic programming (QP) problem. As the real‐time QP solver, a primal‐dual neural network (PDNN) based on linear variational inequalities (LVI) is developed as well with a simple piecewise‐linear structure and global exponential convergence to optimal solutions. Since the LVI‐based PDNN is matrix‐inversion free, it has higher computational efficiency in comparison with dual neural networks.
Computer simulations performed based on the PUMA560 manipulator illustrate the validity and advantages of such a bi‐criteria neural optimal motion‐control scheme for redundant robots. Copyright © 2009 John Wiley & Sons, Ltd.
Developing a novel alkaline anion exchange membrane derived from poly(ether‐imide) for improved ionic conductivity
Authors: Wang Guigui , Weng Yiming , Zhao Jun , Chu Deryn , Xie Dong , Chen Rongrong 
Published: June 2009

AbstractWe have developed a novel alkaline anion exchange membrane derived from poly(ether‐imide) for improved ionic conductivity. The effects of several important parameters on the chloromethylation of the membrane were investigated. These parameters included reaction temperature, reaction time, concentration of chloromethylation agent, concentration of polymer, and the amount of catalyst. The quaternization of the synthesized chloromethylated polymer was studied as well. The results show that all the studied parameters exhibited significant impacts on chloromethylation. Among them, the concentration of the chloromethylation agent played a key role in increasing the chloromethyl functional group attachment onto the polymer. It was found that the gelation could be avoided if these reaction parameters were controlled. It was also found that using an appropriate quaternization approach could significantly improve the ionic conductivity and optimize the conductivity of the membrane even though the functional chloromethyl groups attached to the polymer are limited. Copyright © 2009 John Wiley & Sons, Ltd.