bluuebunny/crossref_metadata_2025_split huggingface dataset:
Strategies of Coexistence of Two Species: Erpobdella octoculata and E. vilnensis (Hirudinea: Erpobdellidae)
Authors: Schenková Jana , Jarkovský Jiří , Helešic Jan 
Published: August 2007

AbstractPopulations of Erpobdella octoculata and E. vilnensis were studied monthly over two years (May 1999–April 2001) at four sampling points on the river Rokytná (Czech Republic). The water depth and velocity were measured and the Froude number for each sample was calculated to follow flow conditions above the bottom. Temporal differences in biomass of the two species were studied by comparing their wet weights and evaluated by the time series analysis; differences in their diets were evaluated by gut content analyses. Significantly different hydrodynamic preferences for juvenile and adult stages of E. octoculata and E. vilnensis were recorded. In E. vilnensis only, an annual cycle was recorded with a one‐month shift of mean weights compared to E. octoculata. This shift, together with the correlation of the leeches wet weights with their prey sizes and their distinct habitat preferences are suggested as mechanisms that explain their coexistence. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Erratum: Symmetry, XPD, and port isolation in an ACMPA array with dual linear polarization
Authors: Torres‐Sánchez Roberto , Casares‐Miranda Francisco P. , Márquez‐Segura Enrique , Otero Pablo 
Published: August 2007

AbstractOriginally published Microwave Opt Technol Lett 49: 1722–1727, 2007. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2886, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22803
Erratum: Application of the Foldy‐Lax multiple scattering method to the analysis of vias in ball grid arrays and interior layers of printed circuit boards
Authors: Ong C.‐J. , Tsang L. 
Published: August 2007

AbstractOriginally published Microwave Opt Technol Lett 49:225–231. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2887, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22804
Design considerations of a broad band microstrip antenna with embedded negative capacitor loading
Authors: Kaya Adnan 
Published: August 2007

AbstractIn this article, effects of negative capacitor loading on the bandwidth (BW) and efficiency of a rectangular microstrip antenna (RMSA) have been investigated. The active negative capacitor is made of a field‐effect transistor that exhibits negative resistance as well as capacitance. It can, therefore, compensate the loss of an inductor having antenna. A single negative‐capacitor‐loaded RMSA gives broadband frequency operation with broadband radiation. A microstrip patch operating at 10.5 GHz having 12.22% BW has been utilized as a reference antenna. Theoretical results for the impedance and the radiation patterns have been presented. It is also shown that the impedance BW of the antenna has been enhanced by using active negative capacitance networks from 12.22% to 16.96%, respectively. In addition, it has been shown that active compensation significantly improves the radiation pattern. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2651–2656, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22806
An advanced RFID system to avoid collision of RFID reader, using channel holder and dual sensitivities
Authors: Chung Harrison B. , Mo Heesook , Kim Naesoo , Pyo Cheolsig 
Published: August 2007

AbstractRecently, RFID system has become popular and has been growing rapidly. Due to using many readers in limited area, RFID reader collision problem occurs when the reader is interfered with the signals from neighbor readers or other devices. Even if 50 channels are available in North America, 15 channels in Europe and 25 channels in Korea are available. Moreover, in the future, if many mobile (cellular) RFID readers might be used in limited area simultaneously, the number of channels is not enough, and the collision problem might be more serious. Therefore, this paper proposes an advanced RFID system with a channel holder and dual reader sensitivities/reduced reader output power. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2643–2647, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22808
Surface character of laser assisted wet chemical etching of YBCO high temperature superconducting film
Authors: Liu Juan‐Xiu , Yang Kai , Liu Lin , Bu Shi‐Rong , Luo Zheng‐Xiang 
Published: August 2007

AbstractThe laser assisted wet chemical etching technology was proposed in this study to apply in the etching of YBCO high temperature superconducting film, which was an intercrossing application involving superconducting electronics, laser technique, and chemistry. The etched surfaces and change characteristics were studied and some important experimental results were reported, including the influences of laser density, etching duration, and direction of LaAlO3 underlay on the etching characters of YBCO film under laser radiation. The main experimental results are as follows: the etching rate of YBCO film is accelerated dramatically under laser radiation and the rate is increased over time; the etching rate is relative with the laser power density; there is no strict boundary under the whole laser facula and the surface etching degree of YBCO film changes gradually; the etched surface characteristics are greatly influenced by the direction of LaAlO3 underlay. The laser assisted wet chemical etching technology of YBCO film can overcome the defect of common wet and dry ion etching technology, and probably becomes the main etching technology of YBCO film. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2672–2675, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22809
A Ka‐band equal‐branch waveguide power divider
Authors: Guo Yunchuan , Xu Yuehang , Xu Ruimin 
Published: August 2007

AbstractA Ka‐band equal‐branch waveguide power divider is proposed in this letter. This waveguide power divider has the uniform main guide and all the branches in same size to minimize the difficulty and sensitivity in the mechanical fabrication. Full‐wave simulation and in‐door measurement are also carried to validate this design. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2637–2639, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22811
Bandpass filter of forked step impedance resonator with harmonic suppression in diplexer applications
Authors: Ho Min‐Hua , Hsu Chung‐I G. , Rao Chen‐Mao 
Published: August 2007

AbstractA novel two‐stage forked stepped‐impedance‐resonator (FSIR) bandpass filter design is presented. The FSIR originated from an SIR has its both open ends split as a fork structure. A tunable zero from the coupled lines is created to suppress the second harmonic of the resonator. Two additional zeros obtained from using the asymmetric tapped‐line feed are used to improve the filter's frequency selectivity. A diplexer design based on the FSIR structure is presented. Experiments are conducted to verify the circuit design. Good agreements between the measurements and the simulations are observed. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2665–2668, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22813
Low‐profile dual‐frequency GPS patch antenna enhanced with dual‐band EBG structure
Authors: Bao X. L. , Ruvio G. , Ammann M. J. 
Published: August 2007

AbstractA novel low‐cost low‐profile dual‐frequency circularly polarized patch antenna for GPS applications is presented. By stacking two square patches with truncated corners on a two‐layer fractal electromagnetic bandgap structure substrate, the coverage of the entire GPS bandwidth is achieved. Two bandgaps exist for the proposed fractal EBG structure, from 1.16 to 1.32 GHz and from 1.45 to 2.10 GHz, which include the lower and upper frequency GPS band. The antenna is low‐profile and has improved gain and axial ratio bandwidth, as well as broader impedance bandwidths compared to the same antenna without EBG. Good circularly polarized radiation patterns are realized. Measurements on prototypes are in good agreement with simulation. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2630–2634, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22815
A method to measure reference strain in FBG strain sensor interrogation system involving actuators
Authors: Rajan Ginu , Semenova Yuliya , Wang Qian , Farrell Gerald , Wang Pengfei 
Published: August 2007

AbstractA method for reference strain measurement for FBG strain sensor in the testing stage while applying strain using actuators like piezo translators or micro screw is introduced. Unlike conventional methods of surface mounting, in our method the strain gauge is affixed directly to the optical fibre, which allows it to use with systems where the strain is applied directly using actuators while testing the FBG sensing system. Different bonding techniques were tested and a comparison with the results from calculated values are presented. Since the contact area between the fibre and strain gauge is very small, a corrected gauge factor is calculated and is used to measure the strain transfer. As a demonstration of the developed method, the strain gauge is used as a reference in an edge filter based FBG sensors interrogation system, where the strain was applied using a micro screw. The measured strain using foil strain gauge affixed to the optical fibre and FBG sensor interrogation system are in close agreement. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2658–2661, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22817
A Clapp LC‐tank injection locked frequency divider
Authors: Jang Sheng‐Lyang , Wu Y.‐J. , Lee Chien‐Feng , Juang M.‐H. 
Published: August 2007

AbstractThe design of a frequency divider (FD) employing 3‐dimensional (3D) inductors fabricated in the 0.18‐μm 1P6M CMOS technology is reported. The FD consists of two single‐ended complementary Colpitts oscillators coupled with capacitors to generate differential output signals. The aim of using 3D inductor is to reduce chip size. The divide‐by‐2 LC‐tank injection locked FD is performed by adding an injection nMOS between the differential outputs of the divider. The measurement results show that at the supply voltage of 1.6 V, the divider free‐running frequency is tunable from 3.05 to 3.52 GHz, and at the incident power of 0 dBm the locking range is about 2.9 GHz (43%), from the incident frequency 5.3–8.2 GHz. The core power consumption is 7.14 mW. The die area is 0.625 × 0.672 mm2. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2625–2628, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22819
On compact printed‐circuit transmission lines
Authors: Djordjević Antonije R. , Djurić Milica D. , Tošić Dejan V. , Sarkar Tapan K. 
Published: August 2007

AbstractFor the purpose of designing miniature microstrip transmission lines and their substitutes we consider various structures and compare their electrical properties and footprint. Straight transmission lines have the best wideband performance, followed by meander lines. Photonic band‐gap structures are inferior. The footprint areas for all structures are similar. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2706–2709, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22822
Compact hollowed printed monopole antenna with extremely wide bandwidth
Authors: Yan Xiao‐Rong , Zhong Shun‐Shi , Wang Guo‐Yu 
Published: August 2007

AbstractA compact hollowed printed monopole antenna with an extremely wide bandwidth is introduced, which is composed of a hollowed elliptical monopole patch and a trapeziform ground plane, both printed on the same side of a substrate, and is fed by a tapered CPW feeder in the middle of the ground plane. The simulated and experimental results agree well and demonstrate that this antenna achieves a measured impedance bandwidth from 0.44 to 10.6 GHz (24.1:1) for VSWR ≤ 2, and exhibits a nearly omnidirectional radiation pattern, while its area is only about 0.20λl
× 0.13 λl, where λl is the wavelength of the lowest operating frequency. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2883–2886, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22829
A hybrid QR factorization with Dual‐MGS and adaptively modified characteristic basis function method for electromagnetic scattering analysis
Authors: Han Guodong , Gu Changqing 
Published: August 2007

AbstractIn this article, a hybrid method of adaptively modified characteristic basis function method (AMCBFM) and QR factorization with a dual modified Gram‐Schmidt (Dual‐MGS) algorithm, which is called QR‐AMCBFM, is presented. The first step is to derive the primary basis functions by using AMCBFM. To get the high‐level basis functions, QR factorization algorithm with Dual‐MGS is used to decompose the mutual coupling matrices. Different threshold values for the near and far field domains are set in the QR scheme. When the numerical rank gotten in the upper program is down to a set threshold, the rest interaction between farther blocks would be ignored. Subsequently, the high‐level characteristic basis functions and the coefficient of current are calculated. Once the adjacent currents precision arrives at a certain criterion, the higher‐level basis functions are thought of unnecessary. The hybrid algorithm estimates adaptively in the entire process. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2879–2883, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22830
A complementary Hartley injection‐locked frequency divider
Authors: Jang Sheng‐Lyang , Lin Che Yi , Lee Chien.‐Feng. , Juang Miin‐Horng 
Published: August 2007

AbstractThis work proposes a new injection‐locked frequency divider (ILFD) based on the differential complementary Hartley VCO topology. At the supply voltage of 1.8 V, the tuning range of the free running ILFD is from 7.54 to 7.94 GHz, about 400 MHz, and the locking range of the ILFD is from 14.94 to 16.05 GHz, about 1.11 GHz, at the injection signal power of 0 dBm. The ILFD dissipates 13.54 mW at the supply voltage of 1.8 V and was fabricated in the 1P6M 0.18 μm CMOS process. The phase noise of the locked ILFD tracks with the low‐phase‐noise injection source. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2817–2820, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22834
Design strategies for dual‐band Class‐E power amplifier using composite right/left‐handed transmission lines
Authors: Thian Mury , Fusco Vincent 
Published: August 2007

AbstractIn this article we propose a technique for dual‐band Class‐E power amplifier design using composite right/left‐handed transmission lines, CRLH TLs. Design equations are presented and design procedures are elaborated. Because of the nonlinear phase dispersion characteristic of CRLH TLs, the single previous attempt at applying this method to dual band Class‐E amplifier design was not sufficient to simultaneously satisfy the minimum requirement of Class‐E impedances at both the fundamental and the second harmonic frequencies. This article rectifies this situation. A design example illustrating the synthesis procedure for a 0.5W‐5V dual band Class‐E amplifier circuit simultaneously operated at 900 MHz and 2.4 GHz is given and compared with ADS simulation. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2784–2788, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22836
Compact designs of a band‐pass filter with novel open‐loop resonators
Authors: Jiang Xin‐Hua , Li Guo‐Hui 
Published: August 2007

AbstractIn this article, several square open‐loop resonators with transmission lines are proposed to design the optimized bandpass filters. A compact microstrip filter using an open‐loop resonator was designed, fabricated and measured. At the center frequency f0 = 1.80 GHz, a 3‐dB bandwidth of 5% can be varied from 1.76 to 1.85 GHz. The filter shows a maximum insertion loss in passband of 0.1 dB. A transmission zero is realized at about 3.1 GHz, and the attenuation at this frequency exceeds 70 dB. When compared with the conventional filters using coupled square open‐loop resonators, the proposed filter has a size reduction of 30%. Good agreement between measurements and simulations are obtained. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2755–2757, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22837
Read range measurement and estimation of 900‐MHz‐band mobile radiofrequency identification (mRFID) system
Authors: Kim Yongjin , Yoon Byung‐Tae , Yoon Ick‐Jae , Kim Youngeil 
Published: August 2007

AbstractThe development of radiofrequency identification (RFID) system for the purpose of tracking and controlling goods and products, and obtaining useful information through transponders (tags) from people and objects are growing very rapidly in modern communication area. One of the most important factors of the RFID system is a read range. The read range depends on the several factors, such as transmitting power, antenna gains, receiver sensitivity, environmental noises, etc. In this paper, the read ranges of a commercial RFID system with various internal antennas are measured. The read range estimation based on a radar equation and radar cross section (RCS) estimation is introduced. The estimated read ranges of 900‐MHz‐band mRFID system are compared with the measured read range. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2753–2755, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22838
Band switching matching networks for SiGe 2.4/5.2/5.8 GHz dual‐band three‐mode low noise amplifier
Authors: Chiou Hwann‐Kaeo , Yeh Ping‐Chun , Lin Cheng‐Chieh , Deng Joseph D.‐S. 
Published: August 2007

AbstractA dual‐band three‐mode low‐noise amplifier was demonstrated by using 0.35‐μm SiGe BiCMOS technology. For dual‐band applications, a band switching matching network controlled by MOSFET switches was introduced. Through setting On/off of two MOSFET switches, the proper matching networks were arranged at either 2‐ or 5‐GHz band for dual‐band three‐mode LNA design. The fabricated chip was measured on an FR‐4 in 2.4‐, 5.2‐, and 5.8‐GHz bands, which achieved a power gain better than 15 dB, a noise figure of 4.2 dB, input/output return losses of 9 dB, and an input P1dB of −23.5 dBm. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2717–2721, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22840
A distributed amplifier with 12.5‐dB gain and 82.5‐GHz bandwidth using 0.1 μm GaAs metamorphic HEMTs
Authors: Jeong Jinho , Kim Sung‐Won , Choi Wooyeol , Seo Kwang‐Seok , Kwon Youngwoo 
Published: August 2007

AbstractIn this letter, the monolithic distributed amplifier with active control scheme is presented, using 0.1 μm GaAs metamorphic HEMT technology, with a maximum operating frequency of 315 GHz. Active feedback resistor, which adjusts the negative resistance generated by the cascode gain cell, is employed to maximize the bandwidth of the entire distributed amplifier without oscillation. The measurement of the distributed amplifier with 5 cascode gain cells shows the gain of 12.5 ± 1.2 dB and 3‐dB bandwidth of 82.5 GHz corresponding to the ultrahigh gain‐bandwidth product of 347 GHz. Group delay variation is also measured to be less than ±8.9 ps up to 60 GHz. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2873–2875, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22844
Nonreciprocal left handed coplanar waveguide over ferrite substrate with only shunt inductive load
Authors: Abdalla Mahmoud A. , Hu Zhirun 
Published: August 2007

AbstractA novel ferrite nonreciprocal left‐handed (LH) transmission line is presented. The proposed structure is composed of a coplanar waveguide over a ferrite substrate, horizontally magnetized and periodically loaded with only shunt inductors. The line has a nonreciprocal LH propagation with transmission level better than −5 dB with isolation level up to 20 dB over a moderate bandwidth. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2810–2814, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22848
Experimental investigation of optical thyristor operating as optical hard‐limiter
Authors: Kang Tae‐Gu , Choi Dong‐Muk , Choi Woon‐Kyung , Choi Young‐Wan , Kim Seong‐Joo , Choi Woo‐Kyung 
Published: August 2007

AbstractWe demonstrate the optical thyristor operating as optical hard‐limiter (OHL) in the optical channel and AND gate logic element (AGLE). The oxidized PnpN vertical‐cavity laser (VCL)–depleted optical thyristor (DOT) clearly shows the nonlinear s‐shaped current‐voltage and lasing characteristics. A switching voltage of 5.24 V, a holding voltage of 1.50 V, and a threshold current of 0.65 mA is measured, making these devices attractive for optical processing applications. The VCL–DOT operating as OHL would enhance the system performance because it would exclude some combinations of interference patterns from causing errors as in all previous works. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2779–2780, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22850
Scattering and absorption of electromagnetic waves on a plane with hemispherical bosses
Authors: Gu Xiaoxiong 
Published: August 2007

AbstractWe apply multiple scattering equations to study the scattering of electromagnetic waves on a perfectly conducting plane surface with a random dense distribution of hemispherical bosses. We derive a multipole solution up to third order to analyze close range interactions between nearby bosses. Results show significant improvement of accuracy compared with the traditional dipole approximation solution. Absorption on a lossy embossed surface is obtained from the field solution for the perfectly conducting surface. The surface current and absorption enhancement factor are further computed numerically. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2681–2686, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22855
Magnetically tunable microstrip linear resonator on polycrystalline ferrite substrate
Authors: Pourush Rajeev , Jangid Ashok , Tyagi G. S. , Srivastava G. P. , Pourush P. K. S. 
Published: August 2007

AbstractA low cost conventional half‐wave microstrip linear resonator has been designed at 2 GHz central frequency and fabricated photolithographically by depositing metallic films on prepared LiMnTi polycrystalline ferrite substrate. Resonator characteristics have been examined by keeping it in the low biasing magnetic field values (from 0 to 298 Guass) applied in transverse direction of wave propagation and normal to ground plane. Tunability of 339 MHz (17%) was achieved which is the best reported so far for such a structure for low magnetic field values with a minimum insertion loss of 10.68 dB. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2868–2870, 2007; Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/mop.22858