bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced One‐ and Two‐Photon Excitation Emission of a Porphyrin Photosensitizer by FRET from a Conjugated Polyelectrolyte
Authors: Wu Chuanliu , Xu Qing‐Hua 
Published: December 2008

AbstractPorphyrin‐based systems are widely used as photosensitizers for photodynamic therapy, photocatalysis, and drug release. Strategies to enhance one‐ or two‐photon excitation emission of porphyrin sensitizers have been of great interest and significance. Here we report an electrostatic assembly, which comprises a cationic conjugated polyelectrolyte, PFP, and a negatively charged hematoporphyrin (HP). An enhancement of over 9‐fold in the HP emission intensity for one‐photon excitation Förster resonance energy transfer (FRET), and an enhancement factor of 30‐fold for two‐photon excitation FRET were obtained. This electrostatic assembly can be easily modified in the future to construct DNA‐ or protein‐programmed enhancement of porphyrin emission, which will be of great interest in porphyrin‐based applications.magnified image
Theoretical Derivation of the Molecular Weight Distribution of End‐Capped Linear Condensation Polymers
Authors: Knoester Henk 
Published: December 2008

AbstractEnd‐capped, low molecular weight polymers have found numerous practical applications. By providing the end‐capper molecules with specific chemical functionality, the polymer material can be equipped with a desired chemical behavior for product application or polymer processing. Using probabilistic methods, formulas are derived for calculating the target molecular weight distribution and its averages for the case of linear condensation polymerization. The formulas are generally applicable, allowing for arbitrary amounts of monofunctional monomers or end‐capper molecules affecting either one or both functional groups involved in the polymerization process.magnified image
Complexity as a constraint on firm expansion within and across industries
Authors: Hutzschenreuter Thomas , Guenther Fabian 
Published: December 2008

AbstractWith this paper, we want to shed light on factors influencing a firm's rate of expansion. We argue that expansion is a complex task and complexity associated with expansion projects in one period can negatively impact rate of expansion in the following period. Moreover, we argue that firm portfolio complexity also slows down further expansion. Using longitudinal data on the expansion path of 91 German companies, we show that added product scope of expansion and degree of internationalization characterizing expansion in one period as well as level of product and international diversity have a significant impact on slowing down rate of expansion in the subsequent period. Copyright © 2008 John Wiley & Sons, Ltd.
Design of a compact CPW bandpass filter used for UWB application
Authors: Ye Chang‐Sin , Su Yan‐Kuin , Weng Min‐Hang , Hon‐Kuan  , Syu Jheng‐Jie 
Published: December 2008

AbstractIn this paper, design of a compact coplanar‐waveguide (CPW) bandpass filter (BPF) for low band (3–5 GHz) of ultra wide band (UWB) application is presented. The filter has design freedoms to obtain the proper bandwidth by tuning the frequencies of the transmission zeros at the passband edge. The equivalent circuit of the filter is also obtained. The designed filter exhibits a good lower stopband with rejection greater than 20 dB below 2.95 GHz, which can block the interference of other wireless communication system below 3 GHz. The designed CPW‐BPF is investigated numerically and experimentally. Measured results show a good agreement with the simulated analysis. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 298–300, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24028
Highly selective bandpass filters using broadside‐coupled coplanar waveguide directional couplers
Authors: Sánchez‐Soriano Miguel Á. , Torregrosa‐Penalva Germán , Bronchalo Enrique , Coves Ángela 
Published: December 2008

AbstractIn this work, a new type of wideband coplanar bandpass filter with sharp skirts and large stopband is proposed. The filter exhibits a flat response in the passband, and a steep slope and a high rejection in the stopband. The filter design is based on the use of a broadside‐coupled (BC) coplanar‐waveguide (CPW) directional coupler as a transversal filtering section (TFS). This is performed by conveniently loading two ports of the coupler with shunt stubs, so that the signals in the output port interfere in a way that a bandpass filter response is obtained. The suggested filter scheme has been validated experimentally throughout the design, fabrication, and measurement of a wideband coplanar bandpass filter centered at 2.0 GHz, formed by two TFS connected in cascade. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 294–298, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24029
Analysis of stacked V‐slot loaded patch antenna for wideband application
Authors: Ansari J. A. , Singh Prabhakar , Dubey Satya Kesh , Khan R. U. , Vishvakarma Babau R. 
Published: December 2008

AbstractThe analysis of V‐slot loaded antenna stacked with simple patch is carried out using equivalent circuit model. It is found that stacked patch antenna exhibits enhanced bandwidth that depends on various dimensions of the V‐slot. The proposed theoretical results are compared with simulated and reported experimental results which are in good agreement. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 324–330, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24031
Compact 3‐D on‐wafer radiation pattern measurement system for 60 GHz antennas
Authors: Ranvier Sylvain , Kyrö Mikko , Icheln Clemens , Luxey Cyril , Staraj Robert , Vainikainen Pertti 
Published: December 2008

AbstractThis article presents a quasi full 3‐D on‐wafer radiation pattern measurement system for 60 GHz antennas. The measurement of an omnidirectional antenna is reported and shows promising results. The radiation of the probe itself as well as the effects of a connector feeding the antenna are also studied. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 319–324, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24034
Method for the design of low‐loss suspended stripline directional couplers with equalized inductive and capacitive coupling coefficients
Authors: Wincza Krzysztof , Gruszczynski Slawomir 
Published: December 2008

AbstractDesign of directional couplers in an inhomogeneous suspended stripline dielectric structure has been comprehensively investigated. A new design procedure of coupled‐line directional couplers has been proposed in which the equalization of inductive and capacitive coupling coefficients is achieved simultaneously with matching to the desired characteristic impedance and, therefore, the conditions of ideal coupler realization can be approached. To achieve that, a method of modification of the capacitive coupling coefficient in which shunt capacitances are added to coupled lines has been used. The proposed design procedure has been successfully applied to the design of a 3‐dB directional coupler. Results of both calculations and measurements are presented. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 315–319, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24035
Cross‐Vivaldi antenna for breast tumor detection
Authors: Zhang Jingjing , Fear Elise C. , Johnston Ronald H. 
Published: December 2008

AbstractObservation of cross‐polarized reflections has been proposed for radar‐based breast tumor detection. In this article, a novel cross‐Vivaldi antenna is designed and investigated for this application. The antenna performance is examined over the frequency range of 2.2–5.4 GHz. Results obtained through simulations and experiments demonstrate the ability of the antenna to detect tumors in three‐dimensional (3D) breast models. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 275–280, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24037
Novel metallodielectric electromagnetic bandgap structure
Authors: Kelly James R. , Seager Rob D. 
Published: December 2008

AbstractThis article is concerned with a novel microstrip EBG structure, formed by etching a shape into the signal line. Previous publications announced a lumped‐element equivalent circuit for the structure. This article gives simple equations for computing the equivalent circuit element values. The article also announces an effective EBG low‐pass filter. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 311–315, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24038
Lattice‐type balun with enhanced phase characteristic based on organic system on a package technology
Authors: Park Jong C. , Park Jae Y. 
Published: December 2008

AbstractIn this article, lattice‐type LC balanced‐to‐unbalanced (balun) embedded into a multilayered organic package substrate have been designed, fabricated, and characterized for low cost and small size WLAN and Bluetooth applications. To minimize the phase error of the embedded baluns, LC resonator was utilized instead of shunt capacitor used at conventional lattice‐type balun, furthermore, the quality factors and packaging efficiencies of embedded inductors are maximized by using vertically stacked circular geometry. It has the insertion loss of 0.7 dB, return loss of 21 dB, phase imbalance of 5°, and frequency band width ranged from 2.3 to 2.55 GHz. The fabricated balun was significantly reduced in size and volume by using the vertically stacked spiral inductors and MIM capacitors with BTO high DK film. It has a size of 2.7 ×2.5 ×0.66 mm (height). It is promising for various RF system on a package (SOP) products with multi functionalities, small size, and low cost. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 399–402, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24041
A compact dual‐element antenna array for adaptive MIMO system
Authors: Wang Xuan , Du Zhengwei , Gong Ke 
Published: December 2008

AbstractA novel compact dual‐element antenna array is proposed for adaptive MIMO system. By four embedded PIN diodes in the feeding network, the antenna array has three different working states. It can operate as a dual‐element antenna array or work as a single antenna while the unselected antenna is terminated to a lumped matched resistor. As a dual‐element antenna array, it has a −10 dB impedance bandwidth of 595 MHz covering UMTS band with mutual coupling lower than −15 dB in the whole band. The measured radiation patterns show that the radiation property of the selected antenna keeps steady no matter the other antenna is selected or not. The proposed antenna array can achieve antenna selection scheme to adapt to the time‐varying channel conditions. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 348–351, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24044
Low power consumption and high gain ultra‐wide‐band low noise amplifier
Authors: Huang Shou‐Chien , Tsai Cheng‐Hsiu , Hsin Yue‐Ming 
Published: December 2008

AbstractA low power consumption and high gain ultra‐wide‐band (UWB) low noise amplifier (LNA) utilizing a common‐gate stage connected with a common‐source stage by using current‐reused structure is proposed. The implemented LNA exhibits a maximum power gain of 14.2 dB with a total (core) power consumption of 7.2 mW (3.8 mW) under a 1.5 V power supply. A minimum noise figure of 4.1 dB was obtained within 3‐dB bandwidth of 2.7–8.2 GHz. The proposed UWB LNA presents the highest ratio of the power gain to power consumption among the compared papers. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 382–384, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24047
Analysis and applications of a novel cylindrical dielectric core multiconductor transmission‐line structure
Authors: Faria Jose A. Brandão 
Published: December 2008

AbstractA novel inhomogeneous multiconductor transmission line (MTL) device consisting of a solid cylindrical dielectric core with N + 1 equidistant cylindrical thin wires running along the core's peripheral surface, parallel to the core axis, is examined here. The frequency domain properties of the novel structure are revealed with the help of standard MTL modal analysis techniques. A particular application, for example with four wires, is developed by enforcing a full short‐circuit condition at the far end of the line. The input impedance of the device is obtained by considering several options for the wire connections at the near end of the line. Computed results concerning the MTL device show that the proposed structure exhibits sharp selectivity features in the frequency domain. Results are interpreted physically by making use of equivalent two‐conductor line models, which lead to estimated parameter values in excellent agreement with the computed ones. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 374–382, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24049
Reconfigurable scan‐beam hollow patch reflectarray antenna loaded with tunable capacitor
Authors: Hajian M. , Kuijpers B. , Buisman K. , Akhnoukh A. , Plek M. , de Vreede L. C. N. , Zijdeveld J. , Ligthart L. P. 
Published: December 2008

AbstractIn this article, the design concept of an active reconfigurable reflectarray antenna has been proposed and tested. The elementary radiators are hollow patch element loaded with varactor‐diode device in which the reflected phase can be varied. This phase alteration is based on the variation of the diode capacitance which can be achieved by varying the biasing voltage of the active varactor device. By activating these varactor devices, the phase of each antenna element in the array configuration can be adopted dynamically, and consequently, its radiation beam direction can be reconfigured. The advantage of the MEMS switches is the complexity of the integration and continuing beam scanning capability. The reflectarray incorporating active elements has been built and tested at 6.0 GHz. Narrow band multifrequency shared aperture is demonstrated theoretically and experimentally. The performance of the proposed active antenna is excellent, which pioneers the design of arbitrarily reconfigurable antennas. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 367–374, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24050
Ultra‐wideband antenna design using FDTD and double population genetic algorithm
Authors: Zhao Guo‐Hua , Shen Wen‐Hui , Wu Ming‐Liang 
Published: December 2008

AbstractIn this article, a method for the computer aided design of ultra‐wideband (UWB) printed planar monopoles using double population genetic algorithm and finite‐difference time domain (FDTD) is presented. A novel UWB antenna is obtained successfully. The measured return loss shows an impedance bandwidth of 12.75 GHz from 2.75 to 15.5 GHz for VSWR < 2. Moreover, the designed antenna has a good radiation characteristic with peak gains ranging from 0.9 to 6.97 dBi against operating frequencies. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 361–364, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24052
Quadrature and eight‐phase VCOs implemented with SiGe injection locked frequency dividers
Authors: Jang Sheng‐Lyang , Liu Cheng‐Pin , Lee Chien‐Feng , Hsue Ching‐Wen 
Published: December 2008

AbstractThis article proposes a new technique for designing multi‐phase voltage controlled oscillators (VCOs), which were implemented in the standard TSMC 0.35 μm SiGe 3P3M BiCMOS process. The quadrature voltage‐controlled oscillator (QVCO) consists of two direct‐ injection locked frequency dividers (ILFDs) with a tail MOSFET. The 2nd harmonic frequency component at the drain node of tail transistor in one ILFD is injected to the gate of injection MOSFET in the other ILFD to couple the two independent ILFDs. The eight‐phase VCO is also designed with similar technique to couple four differential VCOs. At the supply voltage of 3.0 V, the output phase noise of the QVCO is −118.22 dBc/Hz at 1 MHz offset frequency from the carrier frequency of 2.28 GHz, and the figure of merit is −173.25 dBc/Hz. At the supply voltage of 3.0 V, the total power consumption is 14.4 mW. At the supply voltage of 3.0 V, the output phase noise of the eight‐phase VCO is −116.14 dBc/Hz at 1 MHz offset frequency from the carrier frequency of 2.92 GHz, and the figure of merit is −171.3 dBc/Hz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 395–398, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24053
The research of mix Raman and EDFA amplifier recycling residual Raman pump for amplifier gain efficiency improvement
Authors: Lin Hsiu‐Sheng , Lai Po‐Chou 
Published: December 2008

AbstractWe propose and demonstrate a novel type of mix Raman and Erbium Doped Fiber Amplifier (EDFA) to recycle the residual Raman pump for enhancing the gain efficiency of power. The mix amplifier is to implement the residual Raman pump from the Stimulated Raman Scattering (SRS) of Raman fiber amplifier (RFA), to be recycled in the Erbium doped fiber (EDF) as the pump of the Erbium doped fiber amplifier (EDFA) [Dai et al., IEEE Photon Technol Lett 8 (1996), 1713–1715.1]. The proposed mix amplifier system structure has only one pump source for Raman amplification, and residual Raman pump after the Dispersion compensating fiber (DCF) is recycled for erbium doped fiber as the secondary signal amplification. The proposed mix amplifier structure can improve the total gain efficiency by 19.3 dB, compared with the performance of the only one Raman amplifier. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 358–361, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24055
Temperature‐insensitive refractive index sensor based on tilted fiber Bragg grating
Authors: Miao Yinping , Liu Bo , Tian Shuang , Zhao Qida 
Published: December 2008

AbstractShort‐period fiber Bragg gratings with gratings planes tilted at an angle 8° corresponding to the fiber axis show core mode and a large number of cladding‐mode resonances in transmission. The differences between the cladding‐mode resonance and the core‐mode resonance are used to detect the variation of the surrounding refractive index; this refractive index sensor is immune to temperature effects by experimental demonstrations. After the cladding of the tilted fiber, Bragg grating was etched by the hydrofluoric, TFBGs with different diameters and different‐order cladding modes were investigated; the sensitivity of a TFBG to the external index can be significantly improved by reducing the cladding radius. Enhanced sensitivity and accuracy are achieved when the changes between 1.333 and 1.4532. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 479–483, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24057
A reduced‐size branch‐line coupler for improved LDMOS balanced power amplifiers
Authors: Draskovic Drasko , Koulouzis H. , Budimir D. 
Published: December 2008

AbstractThis article discusses the application of a reduced‐size branch‐line coupler in the design of a LDMOS class‐AB balanced power amplifier at a center frequency of 2.14 GHz. In the proposed balanced configuration, at center frequency a size reduction, improved intermodulation distortion level by 7 dB, and power added efficiency by 5% are achieved, comparing with the balanced configuration with Wilkinson couplers. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 445–448, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24058
Analysis of conductor‐backed coplanar waveguides using adaptive‐network‐based fuzzy inference system models
Authors: Yildiz Celal , Guney Kerim , Turkmen Mustafa , Kaya Sabri 
Published: December 2008

AbstractA method based on adaptive‐network‐based fuzzy inference system (ANFIS) is presented for the quasi‐static analysis of conductor‐backed coplanar waveguides. The ANFIS is a class of adaptive networks which are functionally equivalent to fuzzy inference systems. Four optimization algorithms, hybrid learning, genetic, simulated annealing, and least‐squares, are used to determine optimally the design parameters of the ANFIS. The results of ANFIS are compared with the results of experimental works, quasi‐static and full‐wave spectral domain approaches, conformal mapping technique, and a commercial electromagnetic simulator IE3D. The results of ANFIS models are in very good agreement with the results of other methods and experimental works. When the performances of ANFIS models are compared with each other, the best result is obtained from the ANFIS model trained by the hybrid learning algorithm. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 439–445, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24059
Erratum: Extreme performance TEM horn
Authors: Malherbe J. A. G. 
Published: December 2008

AbstractOriginally published Microwave Opt Technol Lett 50:2121–2125, 2008. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 583, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24060
Low profile and compact size coplanar UWB antenna working from 2.8 GHz to over 40 GHz
Authors: Naeem Khan Salman , Shuai Zhang , He Sailing 
Published: December 2008

AbstractA square monopole coplanar antenna with a circular base is proposed for ultra wideband (UWB) communications. The design parameters are analyzed and optimized to obtain a good performance and the measured return loss below −10 dB is from 2.8 to over 40 GHz. The proposed antenna has advantages of low profile, small size, UWB, and omni‐directional pattern. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 408–411, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24062
A novel polarization reconfigurable ring‐slot antenna with frequency agility
Authors: Zhao Yu‐Long , Jiao Yong‐Chang , Zhao Gang , Weng Zi‐Bin , Zhang Fu‐Shun 
Published: December 2008

AbstractA novel reconfigurable ring‐slot antenna with switchable polarization and frequency agility is presented. Circular polarization (CP) radiation of the proposed antenna is achieved by introducing proper asymmetry in the ring‐slot structure and feeding the ring slot using a microstrip line at 45° from the introduced asymmetry. Two diodes are used to reconfigure the structure of the ring slot. Switching between right‐hand and left‐hand CP is achieved by turning the diodes on or off and the two CP modes are operated at different frequencies. Moreover, the antenna has a simple structure, which is easier to be fabricated. An antenna prototype is implemented and the measured results are shown. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 540–543, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24064