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Title: ACES Journal August 2015 Cover
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: ACES Journal August 2015 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: ACES Journal August 2015 Full
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Application of Ant Colony Optimization Algorithm to Pattern Synthesis of Uniform Circular Antenna Array
Abstract: The radiation pattern of the antenna arrays is most important problem in communications technology. In this paper, the optimization of uniform circular antenna array is efficiently solved by ant colony optimization (ACO) Method. The proposed method of optimization is used to determine the suitable cost function which leads to achieve the maximum reduction in side lobe level and provide the maximum directivity towards the direction. To optimize the desired antenna array pattern also one parameter is considered to be optimized which is the angular position of each element.
Author(s): A. S. Zare, S. Baghaiee
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Space-Frequency Domain Iterative Method for Modes Analysis of Planar Waveguides
Abstract: We describe a space-frequency domain iterative algorithm to analyze the modes of planar optical waveguides. The one dimensional Maxwell equation was transformed into space-frequency domain by Fourier transform, and became an integral equation which could be solved by an iterative method. For any refractive index profiles, the effective index and mode field distribution are given simultaneously. The numerical result shows that this method is accurate and flexible for planar optical waveguides with any structure.
Author(s): L. Bingxin, Z. Baorong
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Detect and Pointing Algorithm's Performance for a Planar Smart Antenna Array: A Review
Abstract: An adaptive antenna array combines the signal of each element, using some constraints to produce the radiation pattern of the antenna, while maximizing the performance of the system. Direction of arrival (DOA) algorithms are applied to determine the directions of impinging signals, whereas beamforming techniques are employed to determine the appropriate weights for the array elements, to create the desired pattern. In this paper, a detailed analysis of both categories of algorithms is made, when a planar antenna array is used. Several simulation results show that it is possible to point an antenna array in a desired direction based on the DOA estimation and on the beamforming algorithms. A comparison of the performance in terms of runtime and accuracy of the used algorithms is made. These characteristics are dependent on the SNR of the incoming signal.
Author(s): T. Varum, J. N. Matos, P. Pinho
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Integrated Bluetooth and UWB Antenna with Single Band-Notched
Abstract: A novel integrated Bluetooth and ultrawideband (UWB) antenna with single band-notched is proposed in this paper. The operating frequency ranges of the proposed antenna is 2.3 GHz - 2.56 GHz, 2.96 GHz - 5.11 GHz and 5.95 GHz - 11.44 GHz, which covers Bluetooth (2.4 GHz - 2.484 GHz) and UWB (3.1 GHz - 10.6 GHz) band, besides the range of IEEE 802.11a WLAN (5.15 GHz - 5.825 GHz) with VSWR less than 2. Its main part consists of a hexagonal geometry, an L-shaped strip and two mushroom-like electromagnetic band gap (EBG) cells. The performance of the antenna is simulated and optimized by CST Microwave Studio and the simulated results meet the design requirements well.
Author(s): Z. Han, Z. Ma, Q. Xue
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Modification of Vivaldi Antenna for 2-18 GHz UWB Application with Substrate Integration Waveguide Structure and Comb Slots
Abstract: In this paper have been developed two new Vivaldi antenna for UWB application at 2-18 GHz with SIW structure for linear phase center labeled as antenna I and antenna II. The proposed antennas have high gain and directional patterns with symmetric radiation pattern in phi=0 and phi=90 planes. The SIW structure is combined with Vivaldi antenna in order to improve the gain, pattern and phase center linearity. Similarly, for gain improvement at lower frequencies for SIW antenna and with less divergence in the gain, slots with comb models are proposed. The prototype antenna is printed and fabricated on Roger 4003 with ?r = 3.45 and thickness of 1.5 mm. The antenna’s total dimension is 120 mm × 160 mm. The simulation and experimental VSWR and the gain of antenna I and II is less than 2.5 and 6 dBi - 15 dBi, and 2.4 for 2.17-18 GHz and 8.2 dBi - 15.5 dBi in the entire frequency range of 2-18 GHz respectively. Likewise, the Vivaldi antenna phase center is investigated and finally the linear characteristic of the antenna phase center is presented with linear variation.
Author(s): F. B. Zarrabi, N. P. Gandji, R. Ahmadian, H. Kuhestani, Z. Mansouri
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Low-Profile Asymmetrical-CSRR-Loaded Stacked Microstrip Patch Antenna
Abstract: By introducing an asymmetrical-CSRRloaded parasitic patch beneath the radiating patch of a traditional low-profile microstrip antenna, a novel stacked antenna with both 22.46% fractional bandwidth, and stable and uniform radiation patterns in the entire operating frequency range is achieved, even the total height is only approximate 0.04?L (where ?L indicates the free-space wavelength corresponding to the lower bound of the operating frequency band). The antenna is designed, fabricated and tested. The experimental results agree with the simulations.
Author(s): M.-C. Tang, T. Shi, H. Xiong, S. Qing
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Band-Notched Compact Rectangular Ring Antenna Using Triple Omega-Shaped Structures for UWB Systems
Abstract: In this letter, a new ultra wideband monopole antenna with frequency band-stop function is designed and manufactured. The antenna contains a rectangular ring radiating patch and a partial ground. In the structure, by etching a ?-shaped slot on the ground plane, extra resonance is excited and therefore more extended impedance bandwidth can be achieved. In order to create band-rejected function, a ?-shaped sleeve into the rectangular ring patch and an inverted ?-shaped slot on it and feed-line are used. The measured results depict that the antenna is able to cover the bandwidth from 2.6 to 10.4 GHz for VSWR ? 2 excluding the rejected bands from 3.1 to 3.8 GHz and from 5.0 to 6.0 GHz. Acceptable VSWR and radiation pattern characteristics are earned on the frequency band of interest.
Author(s): M. Akbari, S. Zarbakhsh, N. Rojhani, K. Zendeh bi Zadeh, R. Ghazian
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Compact Quasi-Yagi Antenna for Handheld UHF RFID Reader
Abstract: This paper describes a compact printed Quasi-Yagi antenna for ultra high frequency (UHF) radio frequency identification (RFID) reader that can be used in both Europe and US regions. The proposed antenna is a Yagi type structure with a microstrip-tocoplanar stripline transition, a meander dipole, a folded finite-size ground plane and a rectangle ground plane. The proposed antenna has compact size (0.18?×0.24?). The proposed antenna has an endfire radiation pattern within operation bandwidth, with peak gain values of more than 3 dBi and return loss is less than -10 dB in approximately 100 MHz band that can cover European and US RFID bands (860 MHz - 960 MHz). We described the antenna structure and presented the comparison of simulation results with experimental data. Good return loss and radiation pattern characteristic are obtained, measured results are presented to validate the usefulness of the proposed antenna structure for RFID reader.
Author(s): Z. Du, Z. Wu, M. Wang, J. Rao, P. Luo
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: CPW-Fed Slot Antenna for Major Wireless Communication Systems
Abstract: In this paper, we present a new co-planar waveguide (CPW)-fed slot antenna for wireless communication systems. The proposed antenna is fabricated on an FR4 substrate with dielectric constant of 4.4. Configuration of the antenna structure is based on S-shaped structures in both of the radiating stub and ground plane where it operates over a very wide bandwidth and improves the impedance matching. By converting the S-shaped structure at the antenna radiating stub, a new resonance at the lower frequencies is generated, and also by converting the ground plane to the modified S-shaped structure, a good multi-band operation and bandwidth enhancement can be achieved. The measured impedance bandwidth of the proposed antenna for 10 dB return loss is from 1.04 GHz to 1.42 GHz and 1.88 GHz to 2.51 GHz, covering the major wireless communication bands like GPS, MDS/WCS, PCS, WiBro, Bluetooth, HiperLAN, and etc. Simulated and experimental results obtained for this antenna show that the proposed slot antenna has a good isolation and radiation behavior.
Author(s): N. Adlband, Y. Ojaroudi
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Frequency Selection for Accurate Radar System of 2D Airplane in Turbulence Using Beam Wave Incidence
Abstract: Selection of the proper frequencies that are able to detect civil and military aircrafts is a challenging issue in radar engineering. Proposed algorithm measures the effect of the linear polarization including H-wave polarization on the radar detection behavior in random medium, and hence, compares it with the E-wave polarization case. Effects of random medium properties on the scattered waves are analyzed. In doing this, laser radar cross section (LRCS) of targets is calculated using a boundary value method with a beam wave incidence. As a result, performance of the backscattering enhancement is studied with the object configuration considering the creeping waves that have an obvious impact, particularly in the resonance region.
Author(s): H. El-Ocla
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Vector Parabolic Equation Method for the EM Scattering from PEC Objects in Half-Space
Abstract: The vector parabolic equation method was widely used to analyze the electromagnetic scattering from electrically large PEC objects in free space. In this paper, it is applied for the analysis of the electromagnetic scattering from PEC objects in halfspace. By introducing both the incident field and the reflected field to illuminate the objects, the vector parabolic equation method can be used to efficiently calculate the radar cross-section of PEC objects with electrically large size in half-space. The numerical results demonstrate that the proposed method can efficiently give reasonably accurate results.
Author(s): Z. He, T. Su, R. S. Chen
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Application of an IE-Based Domain Decomposition Method for Analysis of Planar Microstrip Array Structures: Meshless Approach
Abstract: In this paper, application of an integral equation based domain decomposition method (DDM), developed for numerical solution of one-dimensional Fredholm integral equations of the second kind, is extended to electric field and mixed potential integral equations in two dimensions. Even though the original DDM was developed based on the Nyström method, results of the present work shows that meshfree approach can also be utilized. The extended DDM is employed for efficient meshfree analysis of planar microstrip array structures in the sense of reduced-size shape function and stiffness matrices. Results are validated by method of moments.
Author(s): B. Honarbakhsh, A. Tavakoli
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Study on Crosstalk Between Space Transient Interference Microstrip Lines Using Finite Difference Time Domain Method
Abstract: In the paper, a Carson reciprocity theorembased numerical method is proposed to analyze the crosstalk of space transient interference microstrip lines. Firstly, the proposed method is realized via solving the coupling voltage between the space transient interference and the microstrip lines by the use of Carson reciprocity theorem. Then the crosstalk between the microstrip lines caused by the coupling voltage is studied based on the finite difference time domain (FDTD) method. Lastly, compared with the Baum-Liu-Tesche (BLT) equation method, the proposed method reduces the computational complexity without solving the complex scattering field. In this paper, coupling between a dipole and a microstrip line will be considered and its coupling model will be given. FDTD and the parasitic parameter model between the microstrip lines are used to get the crosstalk. In addition, the crosstalk between the microstrip lines caused by the space transient interference is analyzed in comparison with the impedance match and mismatch of the terminals. The simulated results show that the voltages of the reflection and crosstalk which are on the victim line with mismatched loads are larger than that with matched loads, and the fluctuate time of the signal on the victim line with mismatched loads is over two times than that with matched loads, which help to verify the effectiveness of the proposed method. Moreover, when we analyze the electromagnetic problems on the surface of the arbitrary shaped ideal conductor, the image method is unavailable because the surface of ideal conductor is not infinite, while the analytic method is unavailable either, on account of the boundary of the ideal conductor is irregular. So the conventional approach is difficult to solve the problems, but the proposed method can work well for the problems due to the fact that it has nothing to do with the boundary shape, and it is only connected with the source and its field. Therefore, the proposed method is suitable for a wide range.
Author(s): Y. X. Sun, Q. Li, W. H. Yu, Q. H. Jiang, Q. K. Zhuo
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
Download Link:Click here to download PDF     File Size: 608 KB

Title: Compact Band-Stop X-Band Filter Using Triple Meander-Line-Ring Defected Ground Structures
Abstract: This paper work deals with design and development of compact microstrip band-stop filter (BSF) for radar applications. The microstrip filter configuration consists of a transmission line and a modified ground plane with three meander-line ring defected ground structures (DGS). The proposed microstrip filter fabricated on a Rogers RT/Duroid 5880 substrate with a relative dielectric constant of 2.2 and has a very small size of 10×15×0.635 mm3 . The proposed BSF has a flat impedance bandwidth of 8-12 GHz with an insertion loss which is larger than 35 dB and a return loss which is less than 0.5 dB at the center of the band-stop frequency range. The operating frequencies of the filter can be easily controlled by changing the dimensions of the meander-line rings without changing the area taken up by the structures. The introduced filter has an excellent out-of-band performance. A good agreement between measured and simulated results was obtained. The proposed filters are promising for use in wireless technologies for radar communications due to their simple structure, compact size, and excellent performance.
Author(s): H. Keivani, N. Adlband, Y. Ojaroudi
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Tunable Bandstop Filter with Bandwidth Compensation
Abstract: In this paper, a tunable bandstop filter with bandwidth compensation is proposed. The equivalent circuit model of the tunable capacitor network is presented to study the tunable mechanism. The electric coupling factor of the tunable capacitor network increases while the tunable capacitor increases. This mechanism can be used to compensate the bandwidth of the tunable filter. In our work, semiconductor varactor diode loaded microstrip LC resonator is adopted to design a tunable bandstop filter. Each resonator requires only one varactor diode for both central frequency and resonator coupling coefficient control. The Sparameters and group delays of the tunable bandstop filter are presented. The measurement shows that the -30 dB absolute bandwidth varies from 371 MHz to 305 MHz, while the central frequency of the stopband varyies from 3.195 GHz to 2.285 GHz.
Author(s): Q. Xiang, Q. Feng, X. Huang, D. Jia
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Circuit Model Analysis of a Polarization and Wide Angle Independent Hexagonal Shaped Metamaterial Absorber
Abstract: This paper presents an equivalent circuit model of metamaterial absorber (MA) based on triple hexagonal shaped resonators. This metamaterial unit cell absorber possesses a nearly wide angle perfect absorption of incidence wave and polarization independence. The absorption is occurred in three different frequencies. The absorptivity is as high as 98%, 93% and 94%, at 3.5 (GHz), 4.7 (GHz) and 6.6 (GHz), respectively. The equivalent circuit model of a single hexagonal ring has been extended to the triple band absorber structure. The simulation of the circuit model agrees well with the full-wave simulation, regarding to return loss and absorption. The important features of this method are simple fabrication of metamaterial absorber and maximum absorption in three frequencies. The proposed metamaterial absorber has wide applications such as thermal detector, stealth technology and imaging. Moreover, a very good agreement between simulation and measurement results has been observed.
Author(s): M. B. Ghandehari, N. Feiz, M. Alipoor
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Distributed Signal and Noise Modeling of Millimeter Wave Transistor Based on CMOS Technology
Abstract: This paper presents a complete distributed transmission line signal and noise modeling of millimeter wave CMOS transistor. In this model, the MOSFET transistor is considered as a three-coupled active transmission line structure, exciting by the noise equivalent sources distributed on its conductors. According to the transmission line theory, closed form expressions of the signal and noise parameters for a high frequency CMOS transistor are derived as the function of device width. By using the proposed model, the scattering and noise parameters of a 130 nm MOSFET are computed over a frequency range up to 100 GHz. The results obtained by this approach is compared with the lumped elements model and verified by the simulation results of Cadence SpectreRF simulator.
Author(s): Z. Seifi, A. Abdipour, R. Mirzavand
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Dynamic Modeling of Linear Actuator Using Fuzzy System to Approximate Magnetic Characteristics
Abstract: This paper proposes a dynamic model of a linear actuator using a fuzzy system to approximate its magnetic subsystem. Magnetic characteristics of the linear actuators indicate a nonlinear behavior, making the whole system complex. Deriving an accurate and proper model, results in the implementation of different control methods in the simulation procedure. This research developed dynamic equations of linear actuator with closed type magnetic circuit. Due to high capabilities of fuzzy approximators in the modeling of nonlinear systems, they are employed to approximate the magnetic subsystem of the linear actuator. According to the results, the model described in this paper, shows significant improvements in comparison with the previous models. Moreover, the proposed model apart from the nominal area, could accurately predict the behavior of linear actuator for out of the nominal operation area. This matter is important in transient situations and short-term overloads. High accuracy and performance is obviously demonstrated by comparing experimental and simulation results both in static and dynamic features
Author(s): M. Hassani, A. Shoulaie
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: A New Closed-Form Expression for Dispersion Characteristics of Fundamental Mode of SIW by Least Squares Method
Abstract: A new and accurate closed-form expression is introduced using least squares method (LSM) to calculate propagation constant of substrate integrated waveguide (SIW) at its fundamental mode of operation. The derived equation is a function of geometrical parameters of the structure and accurately estimates cutoff frequency of the dominant mode. The LSM is used to determine the effective width of the SIW structure. A review and comparisons with recently published simulation and measurement results are also provided, which verify the accuracy of the proposed method.
Author(s): M. GH. Alijani, M. H. Neshati
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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Title: Effect of Various Slot Parameters in Single Layer Substrate Integrated Waveguide (SIW) Slot Array Antenna for Ku-Band Applications.
Abstract: Extended study on SIW slot array antenna based on substrate integrated waveguide (SIW) has been proposed in this paper. Unlike recent publications, the effect of offset gap, gap between the slots and the gap between the last slot with the edge of the SIW antenna are extensively studied and effective formulation for proper positioning of the slots has been done. The structure consists of an array of slot antenna designed to operate in Microwave Ku Frequency bands. The basic structure is designed over a dielectric substrate with dielectric constant of 3.2 and with a thickness of 0.782 mm. The design consists of a SIW antenna fed with a microstrip to SIW transition. Multiple slot array effects are also being studied and analyzed using CST full wave EM Simulator. The designs are fabricated and supported with variation of return loss and radiation pattern characteristics due to appropriate slot offset. The analysis is being carried out to support integration to system-on-substrate (SoS) which promises more compact layouts.
Author(s): S. Moitra, P. S. Bhowmik
File Type: Journal Paper
Issue:Volume: 30      Number: 8      Year: 2015
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