bluuebunny/crossref_metadata_2025_split huggingface dataset:
A detailed rainfall climatology for Malawi, Southern Africa
Authors: Nicholson S. E. , Klotter D. , Chavula G. 
Published: February 2013

ABSTRACTThis article presents a detailed analysis of the mean rainfall climatology of Malawi and an overview of interannual variability. Monthly and seasonal means, the seasonal cycle and intraseasonal variability are examined. This includes an analysis of the onset, end and duration of the rainy season. The study reveals two surprising features of the rainfall regime. One is a region with a strong rainfall maximum in the austral autumn along the western shore of Lake Malawi. The second is a brief period of reduced rainfall in mid‐February that appears to signal a shift in the prevailing rainfall and circulation regime. The prevailing atmospheric circulation is markedly different before and after the break, as are the characteristics of the rainy season. Overall, the results indicate that the early (pre‐break) rainy season (December–February) is dominated by tropical influences, the late (post‐break) rainy season (March–April) is dominated by extra‐tropical influences and interannual variability in these two periods is uncorrelated. The results also demonstrate two aspects of interannual variability: the dominant contribution of the MA season and the frequent opposition between northern and southern Malawi.
Do You Have the Guts to Grow During Tough Times?
Authors: Recardo Ronald J. , Toterhi Tim 
Published: February 2013

AbstractToday's business leaders face ever‐increasing global competition and a more robust regulatory environment than ever, and they are doing so in the midst of the most profound financial and economic dislocation of the past 100 years. Too many of them, however, seem to flinch in the face of these challenges by trying to extricate their organizations from the jaws of the Second Great Depression through blanket cost‐cutting measures. Although thoughtful resource allocation is certainly an effective stabilizing force, organizational leaders that seek to expand their businesses must have the courage to reach beyond myopic measures and employ a targeted strategy that leverages the appropriate elements of both internal and external growth engines to increase the top line as well as the bottom line. © 2013 Wiley Periodicals, Inc.
Exploratory use of a satellite cloud mask to verify NWP models
Authors: Crocker Ric , Mittermaier Marion 
Published: February 2013

AbstractSurface observations of cloud cover for routine verification typically come from manual observations (a human observer makes a visual inspection of the observable sky) or from automated instruments (taking a time‐averaged sample of the cloud passing directly overhead). Each observation type has associated limitations. Here a cloud mask field derived from satellite data is examined as an observation type, providing a top‐down view of cloud cover. This paper shows that the satellite cloud mask field can be used to assess details of spatial bias differences between regional numerical weather prediction (NWP) models over the United Kingdom (UK). The Structure‐Amplitude‐Location (SAL) method is used to show how the distribution of cloud within the NWP model domain can be assessed. Finally the satellite cloud mask is used to derive single site observations which can be used to complement the existing surface observation network, or provide total cloud amount guidance in data sparse locations and shows how it could potentially be used to condition surface observational data in the presence of cirrus. © 2013 British Crown copyright, the Met Office. Published by John Wiley & Sons Ltd.
Modulation accuracy of binary phase‐shift keying signal broadcast after injection locking of a resonant tunneling diode microwave oscillator
Authors: Cantú Horacio I. , Romeira Bruno , Figueiredo Jose M. L. , Kelly Anthony E. , Ironside Charles N. 
Published: February 2013

AbstractInjection of a binary phase‐shift keyed signal to a resonant tunneling diode (RTD)‐based microwave oscillator is presented in this article. The locked signal is broadcast through a wireless communications link and also converted from optical to radio frequency domain using a RTD photodetector. Modulation accuracy is evaluated through error vector magnitude and bit error rate using computer software routines. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:705–711, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27403
Compact h‐ring antenna with dual‐band operation for wireless sensors and RFID tag systems in ISM frequency bands
Authors: Ojaroudi Nasser , Ojaroudi Mohammad 
Published: February 2013

AbstractA novel design of dual‐band microstrip‐fed monopole antenna for radio frequency identification (RFID) applications is presented in this article.The proposed antenna is designed to operate at 2.45 GHz, 5.8 GHz (ISM bands), and it is fabricated on the FR4 substrate with dielectric constant of 4.4. By using H‐shaped antenna, we can gave a new resonance at lower frequencies (2.45 GHz), also by embedding H‐shaped slot, the proposed antenna with H‐ring structure can be created and achieves good dual‐band operation. The measured impedance bandwidth for −l0 dB return loss is from 2.05 to 2.83 GHz (33%) and 5.30 to 6.32 GHz (15.0%), covering the 2.4/5.8 GHz RFID operating bands. Simulated and experimental results obtained for this antenna show that the proposed H‐ring monopole antenna has a good antenna gains and radiation behavior within the 2.4/5.8 GHz frequencies. The designed antenna has a small size of 12 × 18 mm2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:697–700, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27404
Enhanced H‐field in HF RFID systems by optimizing the loop spacing of antenna coils
Authors: Sharma Ashwani , Zuazola Iñaki J.Garcia , Gupta Anshu , Perallos Asier , Batchelor John C. 
Published: February 2013

AbstractThis article presents a design study of a coil antenna with enhanced magnetic field (H‐field), aimed to be used as an interrogator in high frequency radio frequency identification. To achieve this, the number of loops of the antenna are refined by optimizing and exploiting the inner area of an initial coil, using distributed loops, unconstrained inductance and comparable Q‐factor (for a fair comparison) with respect to an initial design. The analytical and simulated results show reasonable agreement to validate the design. The enhanced H‐ field of the antenna shows an unconstrained Q‐factor, indicates a potential rise to the interrogating coverage and hence, resulting in more efficient antenna. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:944–948, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27406
Fault analysis: Optical performance investigation of fiber connections using incorrectly cleaved fiber ends
Authors: Kihara Mitsuru , Yajima Yuichi , Watanabe Hiroshi , Toyonaga Masanobu 
Published: February 2013

AbstractIncorrectly cleaved fiber ends, which are not ideal and are uneven, result from the use of a defective fiber cleaver. The optical performance of field installable connections using incorrectly cleaved fiber ends might deteriorate to more than 40 dB for insertion loss and less than 30 dB for return loss. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:941–944, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27407
Analysis of crosstalk between 10 Gb/s x 64 channels in two‐pump fiber optical parametric amplifier
Authors: Callegari Fulvio A. , Marconi Jorge D. , Fragnito Hugo L. 
Published: February 2013

AbstractWe present a numerical study of 64 signals amplified by a two‐pump fiber optical parametric amplifier. The amplifier was alternatively simulated with two fibers with different values of nonlinear coefficient but the same length. The gain remained constant in both cases. The performance of the amplifier is improved when it is designed with the fiber of lower nonlinear coefficient. Also, it was observed that the performance of the amplifier is strongly dependent on channel separation. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:926–929, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27408
Miniaturized dual‐band antenna for wireless local area network
Authors: Lee Jaesuk , Liu Yang , Kim Hyeongdong 
Published: February 2013

AbstractIn this article, size reduction and wide impedance feeding techniques for antenna design are presented.An inductor connected with a main antenna element in series reduced a resonance frequency of the fundamental mode and a size reduction of about 33% was obtained. In addition, a shunt capacitor between the shorting and feed line enhanced the impedance bandwidth to fully cover the required impedance bandwidths of IEEE 802.11 b/g (2.4–2.484 GHz) and IEEE 802.11a (5.15–5.875 GHz) The proposed antenna possesses a very wide impedance bandwidth of 1957 MHz in the range of the 5 GHz band at a VSWR < 2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:850–852, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27411
Smart receiver system of green hybrid antennas
Authors: Jamlos M.F. , Kamarudin M.R. , Malek M.F. , Jusoh M. , Jamlos M.A. 
Published: February 2013

AbstractA hybrid of multiformities receiver system is proposed in this article.The system is developed through a combination of reconfigurable beam‐steering antenna, reconfigurable beam‐shaping antenna, and data acquisition (DAQ) boards. The combination of beam‐steering antenna with beam‐shaping antenna formed a hybrid four‐layer structure with fabricated element plank of rice husk placed between the beam‐shaping antenna's feed line and beam‐steering antenna's radiating element. This four‐layer hybrid and element plank are held together by 5 mm PCB supports at every edge of the antennas forming a stack configuration. The PIN diode switches of both antennas are connected with DAQs to adaptively control the degree angle and beamwidth of the radiation patterns. The activation of either beam‐steering antenna or beam‐shaping antenna depends on the DAQs' Beam Manager memory and the weakest level of received signal strength. When the transmitted signal is coming from the angle of 0°/360°, 90°, 180°, and 270°, its range and angles' location will automatically be detected by the first DAQ that is connected to the beam‐steering antenna. Meanwhile, the beam‐shaping antennas are activated by the second DAQ, to receive the transmitted signal for a longer range at four different gains: 3.6 dB, 7.2 dB, 9.9 dB, and 14.64 dB. Hence, this hybrid receiver system collectively contributes to the well‐developed eight‐multiformity radiation patterns that can be inter‐changed within only 0.01 ms. Furthermore, signal reliability is paramount since the system could self‐elucidate the mutual coupling effects with the aid of rice husk element plank, which acts as a RF absorber. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:800–809, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27412
Compact wideband bandpass filter using two open loop resonators
Authors: Ma Xing‐Bing , Zheng Hong‐Xing 
Published: February 2013

AbstractIn order to obtain a wideband passband filter, a compact filter with two open‐loop resonators has been designed and fabricated, which has introduced two transmission zeros at the passband's upper frequency area.The proposed topology is demonstrated with a design operating at 5.19 GHz with 19.7% bandwidth. More than 20 dB of spurious suppression from 0 to 3.69 and from 6.27 to 9.71 GHz is demonstrated in the experimental results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:915–917, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27415
Orthogonal slit cut stacked circular patch microstrip antenna for multiband operations
Authors: Gupta Surendra K. , Sharma Ashish , Kanaujia Binod K. , Rudra Shekhar , Mishra Ritu Raj , Pandey G.P. 
Published: February 2013

AbstractIn this paper, a novel orthogonal slit cut stacked circular patch antenna (SC‐SCPA) is proposed for multi band operations. The antenna structure is investigated by cutting two pair of orthogonal slits on the upper patch whose effects are studied in terms of the return loss, input impedance, gain, directivity, and radiation pattern. Multiple resonances are observed that too at lower frequency signifying the compactness and multiband nature of the proposed antenna. The antenna is resonating at four operating frequencies 7.4, 9.0, 9.4, and 10.8 GHz, and 27% reduction in size is achieved by slit cut stacked patch antenna. The proposed theory which is verified by simulation and theoretical results is in good agreement with the simulated results obtained by Ansoft's HFSS. The antenna is working in X‐band from 7 to 12 GHz and applications pertaining to this regime are also discussed herein. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:873–882, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27416
Novel hybrid four‐mode microstrip bandpass filter using two paralleled stub‐loaded resonators
Authors: Guan Xuehui , Wang Xiaoyan , Wang Bin , Yuan Ye , Liu Haiwen 
Published: February 2013

AbstractA novel hybrid four‐mode microstrip bandpass filter (BPF) is proposed in this paper.The filter is realized by association of two stub‐loaded dual‐mode resonators. Two similar stub‐loaded dual‐mode resonators are set in parallel. By appropriately arranging the two dual‐mode resonators and the coupling between resonators with the microstrip feed lines, a new hybrid four‐mode BPF is achieved. The even‐ and odd‐mode theory is introduced to minutely analyze dual‐mode resonators. Moreover the circuit model and coupling matrix of the filter are built to further explain the proposed circuit. The proposed BPF is simulated, fabricated, and measured. Two transmission zeros have been achieved in the transition band of the filter, which improve the performance of the filter. The EM simulated and measured results are presented and excellent agreement is obtained validates the design concept. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:840–845, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27418
Broadband left‐handed rectangular waveguide using a shorted stub and twisted E‐plane posts
Authors: Kim Dong‐Jin , Lee Jeong‐Hae 
Published: February 2013

AbstractA broadband left‐handed (LH) waveguide operating above the cutoff frequency is presented. The unit cell consists of one‐shorted stub and two‐twisted posts. The structure induces double loops in the surface currents, resulting in enhanced inductance which broadens the negative permeability region. To analyze the LH properties of the structure, a 2‐port network cross‐connected equivalent circuit is derived. The measured results of the LH waveguide constructed with five unit cells in an X‐band are in good agreement with simulated data and show a good transmission property as well as a broad LH fractional bandwidth of 26.5%. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:835–840, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27419
Triple‐band USB dongle antenna using fractal and shorted loops for WiFi and WiMAX applications
Authors: Chaimool S. , Chokchai C. , Akkaraekthalin P. 
Published: February 2013

AbstractBy coupling a fractal loop resonator onto the back of a loaded‐fractal loop monopole and a shorted loop, a new triple‐band USB dongle antenna has been achieved and presented. The proposed antenna supports WiFi (2.4–2.5 GHz and 5.15–5.875 GHz) and WiMAX (3.4–3.6 GHz) applications. The proposed triple‐band planar antenna consists of a loaded‐fractal loop monopole for the 2.4 GHz band, a shorted loop for the 5.5 GHz band, and a coupled fractal loop resonator for 3.5 GHz band. The antenna has a small size of 10 × 42 × 0.8 mm3, which is suitable for USB dongle. Good return loss and omnidirectional radiation pattern characteristics have been obtained in the all three bands. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:863–866, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27421
Compact wideband harmonic suppressed antenna using non‐uniform cascaded defected ground structure
Authors: Damaj Lana , Lepage Anne Claire , Begaud Xavier 
Published: February 2013

AbstractThis article presents a coplanar waveguide‐fed wideband bowtie antenna with harmonic suppression using non‐uniform cascaded defected ground structure units.The antenna operates between 2 GHz and 5.4 GHz and harmonics are effectively reduced. Its size is only 0.44×0.48 λ02, λ0 being the free‐space wavelength at 2 GHz. Simulation and measurement agree very well. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:829–835, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27422
Low cross‐polarization array antenna with suspended probe‐feed
Authors: Lee Dong‐Jin , Lee Soo‐Ji , Oh Kyoung‐Sub , Yu Jong‐Won 
Published: February 2013

AbstractThis paper describes the development and performance of a 2 by 4 element suspended microstrip patch antenna array with linear polarization. The proposed structure with a new geometrical composition of entire array possesses the advantages of being wide bandwidth, high gain, precise side lobe level control and low cross‐polarization level. The measured antenna has the peak gain 14.12 dBi and the cross‐polarization is lower than −16 dBi within the impedance bandwidth. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:825–829, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27423
Improving the bandwidth of a microstrip antenna with a circular‐shaped fractal slot
Authors: Dholakiya Hitesh L. , Pujara Dhaval A. 
Published: February 2013

AbstractThis article presents the design of a microstrip‐line fed printed antenna with a circular‐shaped fractal slot. It is experimentally verified that such a design results in bandwidth (better than −10 dB return‐loss) enhancement of up to 52.8%. The results of parametric study for different iteration factors (IF) and iteration orders (IO) are also presented. For the proposed design, better than 4 dB gain was practically achieved over a frequency band of 2–6 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:786–789, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27424
Wavelength self‐initialization technique using allocated light paths of WDM‐PON
Authors: Jung Eui‐Suk , Lee Eun‐Gu , Mun Sil‐Gu , Lee Sang‐Soo , Won Yong‐Yuk , Han Sang‐Kook 
Published: February 2013

AbstractA new wavelength initialization technique for WDM‐PON (wavelength division multiplexed‐passive optical network) system is proposed, where it uses allocated light path over optical link. Compared with other techniques, it is expected that the smallest size and the lowest cost for implementing this will be achieved in the real network. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:753–755, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27426
Modeling for opto‐electronic oscillator considering the nonlinearity of microwave amplifier
Authors: Hong Jun , Yang Chun 
Published: February 2013

AbstractA new model is proposed to analyze the oscillation power and phase noise characteristics of oscillation signal in the single‐loop opto‐electronic oscillator (OEO), and then verified by experiments. Compared with previous models, in our model, the nonlinearity of not only the E/O modulator but also the microwave amplifier is included in calculating systematic nonlinearities, so this model can describe OEO more accurately than previous models. Experiments verify the correctness of our model and results show that, compared with previous models, the oscillation power is about 10 dB lower and the minimum single‐sideband phase noise after optimization is ∼3 dB higher in our experiments. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:715–719, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27428
A fully‐integrated CMOS quadrature VCO implemented with balanced VCOs
Authors: Jang Sheng‐Lyang , Chang Chia‐Wei , Lin Yu‐Sheng , Juang Miin‐Horng 
Published: February 2013

AbstractA new CMOS quadrature voltage‐controlled oscillator (QVCO) is proposed. The LC‐tank QVCO consists of two balanced complementary Colpitts VCOs with differential outputs. The tail inductor output of the first balanced VCO is injected to the gate of the tail transistor in the second balanced VCO and vice versa to ensure the two balanced VCOs operate in quadrature. At the supply voltage of 1.2 V, the total power consumption is 4.32 mW. The free‐running frequency tuning range is 13.4%, tunable from 5.92 to 6.77 GHz as the tuning voltage is varied from 0 to 2 V. The QVCO has been implemented with the TSMC 0.18 μm CMOS technology and the die area is 0.843 × 1.024 mm2. The measured phase noise at 1 MHz offset is −121.67 dBc/Hz at the oscillation frequency of 6.74 GHz and the figure of merit of the proposed QVCO is about −191.89 dBc/Hz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:700–703, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27433
A Compact planar diversity antenna for ultra‐wideband application with band‐notched function
Authors: Natarajamani S. , Behera Santanu Kumar , Patra Sarat Kumar 
Published: February 2013

AbstractA compact two‐element diversity planar antenna for ultra‐wideband (UWB) application with band‐notch function is proposed. By adapting two symmetrical rectangular patches with three bevels cutting in the edge of the radiators, the antenna provides wideband impedance matching characteristics over the desired frequency range. The wideband isolation can be achieved through uniform branch length ratio used in the ground plane. Measured S‐parameters show that the antenna is able to cover the entire UWB band from 3.1–10.6 GHz and good isolation of less than ‐25 dB. Also it has a band‐notch function to avoid overlap with the 3.5 GHz WiMAX band. The radiation pattern, realized gain, envelope correlation, and pulse handling capacity are measured. From the results, it is observed that the proposed diversity antenna can be suitable for UWB application. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:758–762, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27435
Design of a miniaturized patch antenna for easy deployment on metal surfaces
Authors: Hinnemo Malkolm , Grudén Mathias , Rydberg Anders 
Published: February 2013

AbstractA small dual‐layer patch antenna designed for placement on a large conducting surface is presented. It uses the surrounding metal as a ground plane in order to reduce its size. The result is a small patch antenna with good radiation qualities in metallic surroundings. It can also be used in applications where shielding sensitive equipment from radiated fields is necessary, by using the shielding as the metal surface. It is constructed for use with the IEEE 802.15.4 standard at the 2.45 GHz ISM band. The lower layer is made in Fr‐4 with standard height and width. This makes eventual serial production cheaper. The antenna has a measured total efficiency between −1.5 dB and −3.6 dB in the frequency range it is designed for. The longest side is 18.35 mm, equaling 14.9% of the wavelength © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:723–727, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27437