bluuebunny/crossref_metadata_2025_split huggingface dataset:
An EM‐coupled dual‐polarized microstrip patch antenna for RFID applications
Authors: Padhi S. K. , Karmakar N. C. , Law C. L. 
Published: October 2003

AbstractThis paper presents the design and development of a compact dual linearly polarized aperture‐coupled microstrip patch antenna array system for radio frequency identifications (RFID) applications. Two different antenna designs, Antenna‐1 and Antenna‐2, for RFID tag and reader applications are presented at the C and S bands, respectively. The antennas use two symmetric coupling apertures to excite two orthogonal modes for dual‐polarization operation. High isolation of the order of −35 dB is obtained by proper selection of the shape and positions of the coupling aperture. The prototype antenna yields a 14.6‐dBi peak gain, a 36° 3‐dB beamwidth (HPBW), a 30‐dB cross‐polarization level, and isolation better than 38 dB between the two orthogonal polarizations (Tx and Rx) at the S band, and a 7.7‐dBi peak gain, a 70° 3‐dB beamwidth (HPBW), a 24‐dB cross‐polarization level, and isolation better than 38 dB between the orthogonal polarization at the C‐band, respectively. The antenna yields a 10‐m identification‐read range in the field trial. The findings are very promising for RFID applications. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 354–360, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11215
2 × 2 Circularly polarized patch antenna arrays with broadband operation
Authors: Wu Jeun‐Wen , Lu Jui‐Han 
Published: October 2003

AbstractBy adopting a sequential rotation technique with the use of an L‐strip microstrip line to feed the proposed patch antenna array, a broadband design for circular polarization (CP) is proposed and experimentally studied. The impedance bandwidth and 3‐dB axial‐ratio bandwidth of the circularly polarized patch antenna arrays presented achieve a 46.8% and 45%, respectively. The measured minimum axial ratio is 0.5 dB for the truncated‐corner square‐patch antenna array operating at 1.4 GHz. Peak antenna gain across the overall operating band is measured to be 10.5 dBi. Details of the proposed broadband circular‐polarization design are described, and experimental results of the constructed prototypes are presented and discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 360–363, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11216
Determination of optimal pumping configuration for an L‐band EDFA with 980‐nm LD and ASE pumps
Authors: Adikan F. R. M. , Mahdi M. A. , Noor A. S. M. 
Published: October 2003

AbstractL‐band gain improvement through amplified spontaneous emission (ASE) pumping was conducted. For an L‐band amplifier system employing ASE to improve gain, pumping the system counterdirectionally with ASE and codirectionally with 980 nm would yield the best overall performance in terms of gain. Gain improvement as high as 6 dB was attained. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 363–366, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11217
Small chip dielectric antenna for Bluetooth application
Authors: Moon Jung‐Ick , Park Seong‐Ook 
Published: October 2003

AbstractThis paper proposes the design of a small chip‐type dielectric antenna using the advanced meander line technique, so that the radiation metals are formed on the bottom face of a ceramic dielectric (8 × 4 × 1.5 mm3, alumina) and on both faces of the substrate (thickness 1.0 mm, FR‐4). The performance of the proposed antenna mode, which remarkably reduced the size, shows good agreement between measured and computed results. The measured results show that this antenna has 11.2% bandwidth (2.35–2.63 GHz, |S11| < −10 dB) and 2.3‐dBi maximum radiation gain, respectively. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 366–368, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11218
Planar‐diversity folded‐dipole antenna for 5‐GHz WLAN operation
Authors: Lee Gwo‐Yun , Chen Wen‐Shyang , Wong Kin‐Lu 
Published: October 2003

AbstractA novel planar‐diversity folded‐dipole antenna, comprising two back‐to‐back folded dipoles separated by a central ground plane, is proposed. Experimental results of a constructed prototype suitable for WLAN operation in the 5‐GHz band, such as the 5.2‐GHz (5150–5350 MHz) and 5.8‐GHz (5725–5875 MHz) bands are presented. The radiation patterns of the two folded dipoles are directional in two complementary half spaces, and thus are capable of providing spatial diversity in order to mitigate the multipath interfering problem for WLAN operation. Details of the antenna design and experimental results are presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 368–370, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11219
A stair‐shaped slot antenna for the triple‐band WLAN applications
Authors: Wang Chien‐Jen , Tsai Wen‐Tsai 
Published: October 2003

AbstractIn this paper, a novel triple‐band microstrip‐fed slot antenna for wireless communication systems operating at 2.4, 5.2, and 5.8 GHz is demonstrated. The slot antenna is originally designed to radiate at 2.4 GHz. By etching a stair‐shaped slot on the ground plane and adding several stubs at the edge to excite the first higher‐order mode, we can create another resonant band at 5 GHz. According to the results, the impedance bandwidths are 227 and 778 MHz at the 2.4‐ and 5‐GHz bands, respectively. In addition, the dimension of the proposed slot antenna is smaller than that of the conventional rectangular‐slot antenna. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 370–372, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11220
A method for characterizing coplanar waveguide‐to‐microstrip transitions, and its application to the measurement of microstrip devices with coplanar microprobes
Authors: Maya M. C. , Lázaro A. , DePaco P. , Pradell L. 
Published: October 2003

AbstractThis paper presents a method for characterizing coplanar waveguide‐to‐microstrip (CPW‐M) transitions by using on‐wafer coplanar (CPW) microprobes. It is based on extracting the transmission matrix of the CPW‐M transition from the measurement of theSparameters of two microstrip transmission lines of different lengths, each of which includes two CPW‐M transitions. To verify the proposed method, theSparameters of a zero‐length line, which is composed of two CPW‐M transitions (“thru” connection) and has not been used in the transition characterization, are measured up to 40 GHz and are compared to those extracted and obtained from electromagnetic simulations. The method is applied to the measurement of a microstrip coupled‐line filter embedded in CPW‐M transitions. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 373–378, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11222
An iterative method for solving a large dense matrix in the method of moments solution of an electrostatic problem
Authors: Singh Ritu , Singh Surendra 
Published: October 2003

AbstractThis paper illustrates the application of Wynn's vector ε‐algorithm to solve a system of equations arising in the method of moments (MoM) solution of an electrostatic problem. Since the method is iterative, it does not require inversion of a matrix. The degree of accuracy of the solution can be controlled by specifying a convergence factor. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 378–380, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11223
Configuration of a stepped impedance bandpass filter
Authors: Wang Xuedong , You Bin , Ji Wusheng , Li Ying 
Published: October 2003

AbstractThis paper describes the design of a compact stripline ceramic filter, using short‐circuit stepped‐impedance resonators (SIRs) to enhance the harmonic stop‐band response. Moreover, this filter has a very small size of 3.6 mm × 3.0 mm × 0.5 mm and a low insertion loss of 0.6 dB in the passband. The filter's response, with a design center frequency of 2390 MHz and 3‐dB bandwidth at 250 MHz (10.4%), shows an increase in the first harmonic frequency to 9004 MHz. At three times the fundamental passband frequency (7160 MHz), stop‐band attenuation is better than −40 dB. The results demonstrate the usefulness of SIRs for improving the stop‐band performance of bandpass filters. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 380–383, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11224
Simple models based on neural networks for suspended and inverted microstrip lines
Authors: Yildiz Celal , Saracoglu Oytun 
Published: October 2003

AbstractThis paper presents new and simple models based on artificial neural networks (ANNs) to determine the effective permittivities of suspended microstrip (SM) and inverted microstrip (IM) lines. The neural results are in very good agreement with the theoretical and experimental results available in the literature for both SM and IM lines. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 383–389, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11225
Smart planar inverted‐F antenna for broadband applications
Authors: Karmakar Nemai Chandra 
Published: October 2003

AbstractA single‐feed dual‐band stacked‐patch Planar Inverted‐F Antenna (PIFA) is integrated with a RF switch array at one side of its shorting straps to make a tunable PIFA. The L‐band switch yields 0.45‐dB insertion loss (IL) and 10‐dB isolation bandwidth (BW) of >100% at 1.2 GHz. The tunable PIFA yields 13% frequency tunability BW at 800 MHz band and 21% BW at the 1.9‐GHz band. The measured radiation patterns are broad beams with low backlobes, as compared to those of a standard PIFA. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 389–393, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11226
Near‐field time‐domain physical‐optics and FDTD method for safety assessment near a base‐station antenna
Authors: Martínez‐Búrdalo M. , Nonídez L. , Martín A. , Villar R. 
Published: October 2003

AbstractAn efficient physical‐optics formulation in the time domain (TDPO), combined with the finite‐difference time‐domain method (FDTD), is presented to evaluate the near scattered field from a base‐station antenna by a surrounding obstacle. This technique is used to demonstrate compliance guidelines related to human exposure to those antennas in its operational environment. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 393–395, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11227
An enhanced 2 × 2 antenna array based on a dumbbell EBG structure
Authors: Jin Nanbo , Yu Ang , Zhang Xuexia 
Published: October 2003

AbstractIn this paper, a novel uniplanar compact EBG structure—a dumbbell structure—is used in the design of a 2 × 2 microstrip antenna array, which has a resonant frequency of 5.6 GHz. Due to the suppression of the surface wave introduced by the EBG structure, the E‐plane mutual coupling between the array elements is reduced, as well as the side‐lobe level in the E‐plane radiation pattern. Moreover, a 1.5‐dB increase in the gain of the main lobe is observed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 395–399, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11228
RF SAW filter package design for wireless communications
Authors: Finch Craig , Yang Xiaomin , Wu Thomas X. , Abbott Benjamin 
Published: October 2003

AbstractThis paper describes a new method to design a ceramic chip and wire package for an RF SAW filter. Both the solid model of the package and bond wires are included in the full‐wave analysis. A novel port configuration is used in finite‐element simulation. Agreement between measurement and simulation is found to be excellent. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 399–401, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11229
Nonlinear phase shifts in the design of comb‐like dispersion‐profiled fiber for pulse compression
Authors: Wang Jianping , Wu Yue , Lou Caiyun , Gao Yizhi 
Published: October 2003

AbstractIn the design of comb‐like dispersion‐profiled fiber (CDPF) for pulse compression, the length of the dispersion shift fiber (DSF) is determined by the nonlinear phase shift of each segment. To achieve a higher compression factor, it is necessary to increase the phase shift experienced by the pulse in each segment. However, a too large phase shift generally results in severe pulse distortion or breakup and the shedding of a large proportion of the pulse energy to a dispersive background level. Pulse‐compression experiments are made with three different CDPFs of different nonlinear phase shifts and a high‐quality compression effect is achieved. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 401–404, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11230
Experimental studies of a slot‐loaded triangular folded planar inverted‐F antenna
Authors: Row Jeen‐Sheen , Ai Ching‐Yuan 
Published: October 2003

AbstractThis paper presents the experimental results of a single‐feed triangular folded planar inverted‐F antenna loaded with a V‐shaped slot. By placing the V‐shaped slot at different positions in an isosceles‐triangular microstrip patch, novel multiband and broadband operations of the proposed antenna can be achieved. Results show that an operating bandwidth of more than 30% is obtained when the slot is placed near the center of the triangular patch and a triple‐band operation is achieved when the slot is close to the edge of the triangular patch. Details of the proposed designs are described and typical experimental results are presented and discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 404–406, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11231
Design of wideband base station antenna arrays for CDMA 800 and GSM 900 systems
Authors: Hui K. Y. , Luk K. M. 
Published: October 2003

AbstractArrays of wideband L‐probe stacked patch antennas are designed for applications in both CDMA and GSM base stations with operating frequency range form 820 to 960 MHz (SWR ≤ 1.5). Different values of antenna gains are achieved with the use of four, six, and eight elements. A set of element separations and phases for each array is found for the excitation of a shaped radiation pattern with null‐filling and upper side‐lobe suppression. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 406–409, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11232
RF parameter extraction of MMIC nichrome resistors
Authors: Sharma Renu , Vinayak Seema , Rawal D. S. , Kumar Ashok , Ray U. C. 
Published: October 2003

AbstractThe lumped‐element electrical equivalent circuit of nichrome (NiCr) resistors is important for monolithic microwave integrated circuit (MMIC) design. This paper presents a methodology for the RF parameter extraction of thin‐film NiCr resistors fabricated on GaAs substrate. An algorithm based on DUT S parameters has been developed to extract the electrical parameters of the equivalent circuit up to 18 GHz for a large number of resistors of varying geometries and geometry‐scaleable curve‐fitted equations for the model parameters have been obtained. The computed S parameters, based on the extracted model parameters, agree reasonably well with the measured S parameters. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 409–412, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11233
A new PBG structure: Corrugated CPW
Authors: Kim S. J. , Myung N. H. 
Published: October 2003

AbstractThis paper presents a new photonic bandgap (PBG) structure with a coplanar waveguide (CPW). The use of slots on the ground prohibits the propagation of the quasi‐TEM mode along the CPW line and provides the two characteristics of stopband periodicity and slot‐depth dependency of the stopband position. We implement two PBG structures which exhibit good performance with compact size. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 412–414, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11234
A 52 GHz VCO with low‐phase noise implemented in SiGe BiCMOS technology
Authors: Jia Lin , Ma Jian‐Guo , Cabuk Alper , Yeo Kiat Seng , Do Manh Anh 
Published: October 2003

AbstractA fully integrated 52‐GHz millimeter‐wave LC voltage‐controlled oscillator (VCO) with −106 dBc/Hz phase noise at 600‐kHz offset frequency and 0.93‐GHz tuning range is reported in this paper using IBM BiCMOS‐6HP technology. The output voltage swing of the VCO is about 0.4 Vp‐p for the complementary cross‐coupled topology with a buffer. A bipolar device is used as the tail transistor to constantly supply a current in order to preserve the oscillation of the VCO. The parasitics due to the interconnected metals are extracted from the layout, and the effects of those parasitics on the VCO's performance are investigated. Based on these analyses, an optimized layout of the complementary VCO is obtained, and the pre‐layout and post‐layout simulations are compared and presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 414–418, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11235
On the design of broadband omnidirectional compact antennas
Authors: Bergmann J. R. 
Published: October 2003

AbstractThe conventional discone antenna is well known as an easy‐to‐build broadband antenna with a vertically polarized omnidirectional radiation pattern. Here, we consider an alternative configuration where both metallic surfaces involved in discone‐type antennas are shaped. A study is performed to find body shapes that simultaneously minimize the antenna's cross‐section area and improve the antenna's performance. For this study, a numerical model based on the method of moments (MoM) is employed and the parameters used to describe the antenna shape are explored. A design example of the modified discone‐type antenna is presented and its performance is compared with that of a conventional discone antenna. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 418–422, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11236
Analysis of different GA strategies applied to antenna far‐fields reconstruction from planar acquisition
Authors: Pérez J. R. , Basterrechea J. 
Published: October 2003

AbstractThe performance of a binary‐coded microgenetic algorithm (GA) applied to planar near‐field antenna characterization is analyzed in this paper. The method replaces the antenna with an equivalent model consisting of short dipoles, whose optimization is carried out using different GA strategies. Results of reconstructed far‐field patterns from synthetic near‐field data and a detailed analysis of the GA‐based approach are included. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 422–426, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11237
Implementation of coupling improvement in coupled lines with different metallization thickness
Authors: Hong Ic‐Pyo , Park Seong‐Kyoon 
Published: October 2003

AbstractIn this paper, we present new types of tightly coupled lines using asymmetrical metallization thickness. A mode‐matching method has been used to analyze this new structure and the simulation results are validated through comparison with the available results. The results in this paper show that the asymmetrical metallization thickness properties of coupled lines can be newly added to the design parameters to improve the tightly coupled characteristics of microwave applications. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 426–428, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11238
A double‐layer FSS structure to suppress far side‐lobes of an antenna
Authors: Shaker Jafar , Cuhaci Michel 
Published: October 2003

AbstractA two‐layer frequency‐selective surface (FSS) is proposed for the suppression of far‐side lobes of radiating elements as an extension of the single‐layer FSS that is used for the suppression of near‐boresight side lobes. Based on the affinity of the proposed structure with the Fabry–Perot resonator, a method is developed for its analysis and design. The limitations of the method of analysis are discussed. A guideline is given for the design of a double‐layer FSS structure for the suppression of far‐side lobes of a radiating structure. A double‐layer filter is designed, fabricated, and used in conjunction with several radiating elements which achieve suppressed side lobes in the angular range of 40°–50° by 15 dB. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 428–432, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11239
Seasonal changes in avian song control circuits do not cause seasonal changes in song discrimination in song sparrows
Authors: Reeves Brendan J. , Beecher Michael D. , Brenowitz Eliot A. 
Published: October 2003

AbstractIn seasonally breeding songbirds, brain nuclei of the song control system that act in song perception change in size between seasons. It has been hypothesized that seasonal regression of song nuclei may impair song discrimination. We tested this hypothesis in song sparrows (Melospiza melodia), a species in which males share song types with neighbors and must discriminate between similar songs in territorial interactions. We predicted that song sparrows with regressed song systems would have greater difficulty in discriminating between similar songs. Sparrows were housed either on short days (SD) and had regressed song circuits, or were exposed to long days and implanted with testosterone (LD+T) to induce full growth of the song circuits. We conducted two experiments using a GO/NO‐GO operant conditioning paradigm to measure song discrimination ability of each group. Birds learned four (experiment 1) or three (experiment 2) pairs of song types sequentially, with each pair more similar in the number of shared song elements and thus more difficult to discriminate. Circulating T levels differed between the SD and LD+T groups. The telencephalic song nuclei HVc, RA, and area X were larger in the LD+T birds. The two groups of sparrows did not differ, however, in their ability to learn to discriminate between shared song types, regardless of the songs' similarity. These results suggest that seasonal changes in the song control system do not affect birds' ability to make difficult song discriminations. © 2003 Wiley Periodicals, Inc. J Neurobiol 57: 119–129, 2003