bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clutter reduction in synthetic aperture radar images with statistical modeling: An application to MSTAR data
Authors: Demirci Sevket , Ozdemir Caner , Akdagli Ali , Yigit Enes 
Published: March 2008

AbstractIn this article, an application of clutter modeling and reduction techniques to synthetic aperture radar (SAR) images of moving and stationary target acquisition and recognition data is presented. Statistical modeling of the clutter signal within these particular SAR images is demonstrated. Lognormal, Weibull, and K‐distribution models are analyzed for the amplitude distribution of high‐resolution land clutter data. Higher‐order statistics (moments and cumulants) are utilized to estimate the appropriate statistical distribution models for the clutter. Also, Kolmogorov‐Smirnov (K‐S) goodness‐of‐fit test is employed to validate the accuracy of the selected models. With the use of the determined clutter model, constant false‐alarm rate detection algorithm is applied to the SAR images of several military targets. Resultant SAR images obtained by using the proposed method show that target signatures are reliably differentiated from the clutter background. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1514–1520, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23413
Inclined slot coupled hemispherical dielectric resonator antenna
Authors: Kakade Anandrao B. , Ghosh B. 
Published: March 2008

AbstractA microstrip line coupled dielectric resonator antenna with an inclined and offset slot in the common ground plane has been analyzed. Excitation of the TE111 mode in this configuration is studied. It is also seen that the slot geometry and offset can be optimized to excite the higher order TM101 mode. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1527–1530, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23414
Multiband planar antenna design for mobile handset
Authors: Sim Chow‐Yen‐Desmond 
Published: March 2008

AbstractThe design of a novel microstrip‐fed planar mobile phone antenna operating within the GSM/PCS/DCS band is proposed. Besides the additional ability to cover the entire wireless local area network frequency spectrum at 2.4, 5.2, and 5.8 GHz, its multiband operation also includes the GLONASS and MSS band if navigation system application is required. Impedance matching for this case is achieved by simply tuning the ground‐plane's width, one side of the taper structure and the tuning stub. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1543–1545, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23418
A coupled‐defected ground structure lowpass filter using inductive coupling for improved attenuation
Authors: Jung S. , Lim Y.‐K. , Lee H.‐Y. 
Published: March 2008

AbstractA coupled‐defected ground structure (C‐DGS) with closely located DGS cells is proposed for the application of high‐performance lowpass filters (LPFs). The closely located DGS cells create the coupling of ground currents between adjacent DGS cells, and the coupling effect greatly improves the stopband characteristics because of an additional attenuation pole without structural modification. A LPF that uses the C‐DGS has an attenuation slope of 110.8 dB/GHz and a −20‐dB rejection band that ranges from 3.8 to 15.6 GHz. The C‐DGS improves the DGS circuit performance and extends the scope of DGS applications. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1541–1543, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23419
An optimized Doherty power amplifier using an unequal quadrature input splitter
Authors: Jung Sung‐chan , Xi Yao , Park Hyunchul , Kwon Sung‐Wook , Van Juho , Lim Kyung‐Hoon , Kim Min‐Su , Cho Hanjin , Jeong Jong‐Hyuk , Yang Youngoo 
Published: March 2008

AbstractIn this article, we present an optimized Doherty power amplifier using an unequal quadrature input splitter and bias control for the peaking amplifier. The linearity and efficiency performances of the Doherty power amplifier were experimentally optimized by means of unequal quadrature input power splitters, which drive unbalanced input power between the carrier and peaking amplifiers. The bias points of the peaking amplifier were also adjusted for each input splitter. A high power‐added efficiency of 33.68% and an output power of 33.95 dBm were achieved for a down‐link wide‐band code division multiple access signal excitation at a given adjacent channel leakage‐power ratio of −30 dBc. This was a significant improvement by 2.75% and 8.22% points from the conventional Doherty and class‐AB amplifiers, respectively. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1536–1539, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23420
An EBG spatial power combiner
Authors: Ooi B. L. , Leong M. S. , Zhong Z. , Wang Y. , Hui S. C. , Hristov H. , Feick R. 
Published: March 2008

AbstractA new electromagnetic bandgap (EBG) spatial power combiner is proposed. The prototype consists of the design of the EBG ground holes structure, the active‐EBG coupler, and the Vivaldi antenna array. A 17 dB system gain coupled with a 5.5 GHz of impedance bandwidth and good out‐of‐band suppression has been achieved. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1534–1536, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23421
Novel design of semi‐circular slot antenna with triple‐band operation for WLAN/WIMAX communication
Authors: Wang Yau‐Der , Lu Jui‐Han , Hsiao Hai‐Ming 
Published: March 2008

AbstractA novel triple‐band design of semi‐circular slot antenna for WLAN/WiMAX communication is proposed. With the use of dual arc‐shaped strips inset along the circle edge of the semi‐circular slot antenna, a new resonant mode close to 3.5 GHz for WiMAX application is easily excited. And, with the excited 2.4‐ and 5‐GHz band of the proposed semi‐circular slot antenna for WLAN applications, the triple‐band operation can be easily achieved. The obtained impedance bandwidths for triple operating bands (2.4/3.5/5 GHz) can reach 310/250/600 MHz, respectively, which is enough for WLAN/WiMAX communication. The peak antenna gains for the operating frequencies across WLAN/WiMAX bands are measured to be, respectively, 4.5, 4.2, and 5.1 dBi with the gain variations within 0.5 dBi. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1531–1534, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23422
Characterizations of a supercontinuum optical source for radio‐over‐fiber system
Authors: Wang Jianping , Liu Bosheng , Wang Dan 
Published: March 2008

AbstractThe generation and characterizations of supercontinuum (SC) optical source in wavelength‐division‐multiplexing radio‐over‐fiber (ROF) system is studied in this article. Factors such as the chirp and peak power of the pump pulse, the length of the SC fiber that affect the light source frequency stability are analyzed. The simulation results demonstrate that by altering the value of initial chirp, peak power and SC fiber length, the random fluctuation of the phase and intensity of the SC spectrum is different. At last by optimizing the initial value, an optimal optical source with high frequency stability as the optical source of ROF system is obtained by experiments. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1561–1565, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23430
A novel high brightness parallax barrier stereoscopy technology using a reflective crown grating
Authors: Chen Chien‐Yue , Chang Ming‐Chieh , Ke Ming‐Da , Lin Chen‐Chi , Chen Yi‐Ming 
Published: March 2008

AbstractIn this study, we propose a method to improve the shortcoming of parallax barrier method. As a result of a great deal of light being absorbed or diffused by barrier, brightness will be seriously decreased. Thus, we recommend an idea to effectively reuse the absorbed light, so that the periodic reflective crown grating is plated and fitted below the barrier. The light absorbed or diffused by barrier will be able to be guided back to the reflected layer in backlight and the re‐guided light can be reused again. After simulation, we find the average brightness of the periodic reflective crown grating is raised 114.47% more than traditional parallax barrier type. And we further measure the brightness of three‐dimensional display composed of the periodic reflective crown grating we designed and a 14 inch LCD panel. It is discovered that the brightness is raised by 96.33%. Besides, we put the metal reflective crown grating in between the liquid panel and the backlight, and this method can effectively avoid the loss of the recycled light reflected, which is absorbed by liquid layer. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1610–1616, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23435
Modified Sagnac interferometer for distributed disturbance detection
Authors: Wu Dong‐Fang , Zhang Tian‐Zhao , Jia Bo 
Published: March 2008

AbstractA fiber optic sensor based on Sagnac interferometer for determining the position of disturbance is presented. For this application, a disturbance simultaneously imposed on two different points of sensing fiber loop could be measured and located. The method solves the problem of isolating part of fiber loop from physical field. Experimentally, longitudinal position of a disturbance is determined with an average error of 59 m over a total length of 25 km. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1608–1610, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23436
X‐band multi function GaAs MMIC for T/R modules in smart antenna applications
Authors: Giannini Franco , Limiti Ernesto , Longhi Patrick E. , Serino Antonio 
Published: March 2008

AbstractThis article presents the design, measurement, and test of a MMIC for the front‐end section of a composite multielement radiating system. The MMIC is composed of a 3‐BIT modified constant phase digital attenuator, a switch, and a pair of amplifiers for TX/RX operation. A uniform linear array can be realized attaching 15 MMICs to the T/R radiating elements. The so obtained array's co‐polarisation pattern is presented. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1667–1673, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23443
Microwave photonic filter inserting an electro‐absorption modulator in a variable polarization beam splitter‐based SAGNAC fiber loop
Authors: Ning G. , Shum P. , Zhou J. Q. 
Published: March 2008

AbstractA coherence‐free microwave photonic filter configuration is presented. It is designed by using a Sagnac interferometer consisting of a variable polarization beam splitter and an electro‐absorption modulator. The variable polarization beam splitter generates π/2 phase difference between the clockwise and counterclockwise waves propagating inside the fiber loop interferometer. Measured results match closely with the theoretical analysis and demonstrate a robust notch filter response. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1665–1667, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23444
A novel dual‐frequency unequal Wilkinson power divider
Authors: Feng Cong , Zhao Gang , Liu Xu‐Feng , Zhang Fu‐Shun 
Published: March 2008

AbstractThis article presents the design of a novel dual‐frequency unequal Wilkinson power divider. This unequal power divider fulfills an arbitrary power split and all the other features of a conventional Wilkinson unequal power divider simultaneously at two arbitrary frequencies. The structure of this power divider and the formulas used to determine the design parameters have been given. Both simulated and measured results of the dual‐frequency unequal Wilkinson power divider are presented to validate our proposed idea. Good experimental performances of the proposed power divider, including an arbitrary power split and a good isolation between the output ports at both frequencies are obtained. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1695–1699, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23447
A 23‐GHz capacitive‐degeneration LC VCO with a FOM of −199 dBc/Hz
Authors: Lee J. Y. , Lee S. H. , Kim H. , Yu H. K. 
Published: March 2008

AbstractIn this article, we presents a fully differential 23‐GHz capacitively emitter‐degeneration double cross‐coupled LC‐tank VCO. The proposed capacitive‐degeneration negative‐resistance cell has higher ftrans and lower input capacitance than conventional cross‐coupled pairs at millimeter‐wave band. The proposed capacitive‐degeneration LC VCO shows low phase noise of −105 dBc/Hz at 100 kHz offset from 23 GHz carrier and wide tuning range of 20.8–24.2 GHz, and consumes 10 mA current. The proposed 23 GHz LC VCO shows a good FOM of −199 dBc/Hz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1688–1690, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23453
Broadband Fabry‐Perot resonator printed antennas using FSS superstrate with dissimilar size
Authors: Liu ZhenGuo , Zhang WenXun , Fu DaoLin , Gu YingYing , Ge ZhiChen 
Published: March 2008

AbstractIn this paper, the broadband Fabry‐Perot resonator antenna composed of single‐layer FSS superstrate with dissimilar size square patch fed by U‐slotted patch is proposed, which is validated by two cases of samples. It is demonstrated that the common bandwidth for (3 dB directivity‐drop and −10 dB returned loss of the Fabry‐Perot resonator antenna with the tapered FSS superstrate increases by 7.99% to 12.2% for two different cases, as compared to that of previously single layer FSS with similar size. At the same time the side‐lobe level of antenna can also be improved.The simulated and measured results are good agreement each other. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1623–1627, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23456
Singularity treatment for integral equations in electromagnetic scattering using Monte Carlo integration technique
Authors: Mishra Mrinal , Gupta Nisha 
Published: March 2008

AbstractA new numerical method is proposed for the analysis of metallic scatterers which can take care of the singular integrals arising in the Method of Moments (MoM) solution for determining the current distribution on the metallic scatterers. The method involves Monte Carlo Integration (MCI) technique in solving the Electric Field Integral Eq. (EFIE). The unknown current distribution is represented in terms of the entire domain polynomial basis functions. It is found that the proposed method is capable of removing the singularity problem arising in the MoM solution of the EFIE very easily and efficiently. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1619–1623, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23457
Divide‐by‐3 injection‐locked frequency divider implemented with active inductor
Authors: Jang Sheng‐Lyang , Tai Chia‐Wei , Lee Chien‐Feng 
Published: March 2008

AbstractThis article presents a wide locking‐range divide‐by‐3 injection‐locked frequency divider (ILFD) employing tunable active inductors (TAIs), which are used to extend the locking range and to reduce die area. The CMOS ILFD is based on a voltage‐controlled oscillator (VCO) with cross‐coupled switching pairs and TAI‐C tanks, and was fabricated in the 0.18‐μm 1P6M CMOS technology. The divide‐by‐3 function is performed by injecting differential signal to the gates of two injection MOSFETs with the drains connected to the VCO outputs and with grounded sources. Measurement results show that at the supply voltage of 1.8 V, the divider free‐running frequency is tunable from 1.20 to 1.284 GHz, and at the incident power of 4 dBm the locking range is about 1.9 GHz (45.2%), from the incident frequency 3.3 to 5.2 GHz. The core power consumption is 12.96 mW. The die area is 0.45 × 0.513 mm2. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1682–1685, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23458
An experimental realization of a fully adaptive smart antenna
Authors: Azaro R. , Ioriatti L. , Martinelli M. , Benedetti M. , Massa A. 
Published: March 2008

AbstractIn this letter, the structure of the prototype of a smart antenna working in the 2.4‐GHz band is described. The radiating structure is composed by an eight‐element linear array with a finite reflecting plane and its adaptive behavior is obtained by means of a set of electronically driven vector modulators that control the array weights. The antenna system is equipped with a control software based on a particle swarm optimizer algorithm that enables the system to adapt to the complex interference scenario. A selected set of numerical and experimental results are reported and discussed to assess the effectiveness of the proposed architecture. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1715–1716, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23459
A novel compact branch‐line coupler using four coupled transmission lines
Authors: Nosrati Mehdi , Karbasi Valashani Salman 
Published: March 2008

AbstractA compact branch line coupler (BLC) using four coupled transmission lines is introduced. The loaded part of the proposed model has a same performance with a cascade two unit elements and it is equaled by a quarter wavelength line. The quarter wavelength lines of each branch in the conventional coupler are replaced by an equivalent circuit composed of a four coupled transmission line and two transmission lines. A compact branch‐line coupler (BLC) is designed, analyzed, and tested using this technique. The size reduction is about 65% with comparable performance. The measurement results are in good agreement with the theoretical ones. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1712–1714, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23460
Electronically tunable pulse generator with programmable pulse repetition rate for 6.0 8.5 GHz ultra‐wideband communications
Authors: Seifarth Christoph , Heynicke Ralf G. , Scholl Gerd 
Published: March 2008

AbstractAn ultra‐wideband (UWB) carrier based pulse generator with tunable carrier frequency for 6.0–8.5 GHz UWB communications compliant to European and United States indoor regulations is presented. Pulses with a pulsewidth of 2.5 ns are generated using D‐type flip‐flops and are upconverted by a frequency mixer and a tunable voltage controlled oscillator providing a carrier frequency of 6.6–7.9 GHz. For the generation of pulse trains, a pulse repetition rate of up to 333 MHz is realized using a programmable clock multiplier offering optional spread spectrum clocking to smooth the output spectrum. Suitable modulation formats are pulse position modulation and on‐off‐keying which can be easily implemented by changing baseband data. Measurement results in time domain and frequency domain are presented showing the functionality of the fabricated device and its conformity to European and US UWB regulations. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1649–1651, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23462
Linear optical amplifier‐based semiconductor fiber ring laser with 93‐nm tuning range
Authors: Qureshi K. K. , Tam H. Y. 
Published: March 2008

AbstractWe propose a simple configuration of a traveling wave tunable semiconductor fiber ring laser. The proposed laser can be tuned over 93 nm with an output power of 1.3 dBm using a thin film fiber Fabry Pérot filter. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1702–1704, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23469
Interdevice isolation characteristics for design and fabrication of 60‐GHz WPAN SoCs
Authors: Kim Sungil , Lee Chul‐Wook , Yun Suck‐Won , Kang Kwang‐Yong , Lee Hai‐Young 
Published: March 2008

AbstractThe high interdevice isolation levels is one of the key technologies in the design and fabrication of 60‐GHz WPAN SoC. To obtain proper interdevice isolation levels, we have analyzed and measured substrate coupling effects with various isolation techniques like a trench and implant structure. From the analyzed and measured results, the feasibility of the implant has confirmed to be applicable to the mm‐wave SoC, and also derived an equivalent circuit form these results, which can be helpful to the design and fabrication of the 60‐GHz WPAN SoC. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1699–1702, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23470
Reconfigurable un‐equal division power divider with the compact size for high efficiency power amplifiers
Authors: Jeong Jinho , Hyeong Park Chan 
Published: March 2008

AbstractIn this letter, a reconfigurable un‐equal division two‐way power divider with the compact size is presented for high efficiency power amplifiers. It is based on the Wilkinson power divider of which the quarter‐wave long lines are replaced by coupled lines. Two ends of each coupled line are terminated with switches which provide the two modes of operation, or two‐way power divider and one‐way transmission line. These switches are used to adjust the characteristics of the coupled line in order to allow the good insertion and return loss performance in both modes. At the design frequency of 2.14 GHz, the fabricated 1:2 power divider showed the input return loss (S11) of −23.0 dB, isolation (S32) of −27.2 dB, and insertion loss of −5.05 dB (S21) and −2.25 dB (S31) in the power divider mode. The insertion loss (S21) was measured to be −0.90 dB with the return loss (S11) of −21.1 dB in the power transmission mode. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1662–1665, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23471
Iterative GRAPPA (iGRAPPA) for improved parallel imaging reconstruction
Authors: Zhao Tiejun , Hu Xiaoping 
Published: March 2008

AbstractIn this work an iterative reconstruction method based on generalized autocalibrating partially parallel acquisitions (GRAPPA) reconstruction is introduced. In the new method the reconstructed lines are used to reestimate and refine the weights from all the acquired data by applying the GRAPPA procedure iteratively with regularization. Both phantom and in vivo MRI experiments demonstrated that, compared to GRAPPA, the iterative approach reduces parallel imaging artifacts and permits high‐quality image reconstruction with a relatively small number of calibration lines and slight changes of GRAPPA weights. Magn Reson Med 59:903–907, 2008. © 2008 Wiley‐Liss, Inc.