ACES Publication Search
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| Title: | ACES Journal February 2016 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2502 KB |
| Title: | ACES Journal February 2016 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 102 KB |
| Title: | ACES Journal February 2016 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 12353 KB |
| Title: | Microwave Imaging Using Synthetic Radar Scheme Processing for the Detection of Breast Tumors |
| Abstract: | Microwave imaging of the human breast for detection of possible tumors is studied by applying the method of synthetic radar imaging using both simulation and theoretical results. The breast is modeled as a homogeneous medium having complex dielectric constant, while the tumor is modeled as a small spherical inhomogeneity. A flexible bow-tie antenna excited by a narrow-band pulse illuminates the breast and the reflected field is monitored as the antenna takes a number of discrete positions along the breast surface. The collected data is processed in a synthetic radar scheme to image the interior of the breast. Simulation results for tumor response are obtained and compared with theoretically obtained results. It is shown that a tumor of few millimeter radius, between 3 to 7 mm, can be detected and located with reasonable resolution. It is found that the tumor response increases with the tumor size at a given frequency band in an oscillatory fashion. |
| Author(s): | A. K. Alqallaf, R. K. Dib, S. F. Mahmoud |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 626 KB |
| Title: | Probe Position Errors Corrected Near-Field – Far-Field Transformation with Spherical Scanning |
| Abstract: | Two effective approaches to correct known positioning errors in a near-field – far-field (NF–FF) transformation with spherical scan for electrically long antennas are proposed and validated numerically and experimentally. They rely on a nonredundant sampling representation of the voltage acquired by the probe, obtained by assuming that the antenna under test is enclosed in a cylinder ended in two half-spheres. The former approach exploits the singular value decomposition method, to retrieve the NF data at the points fixed by the sampling representation from the acquired irregularly spaced ones, and can be used when the nonuniformly spaced samples lie on nonuniform parallels. The latter employs an iterative technique, which can be adopted even if such a hypothesis is not satisfied, but requires the existence of a one-to-one correspondence associating at each uniform sampling point, the nearest nonuniform one. Once the uniform samples have been recovered, the NF data needed by the classical spherical NF–FF transformation are efficiently evaluated via an optimal sampling interpolation algorithm. |
| Author(s): | F. D. Agostino, F. Ferrara, C. Gennarelli, R. Guerriero, M. Migliozzi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2128 KB |
| Title: | Dissipation Factor and Permittivity Estimation of Dielectric Substrates Using a Single Microstrip Line Measurement |
| Abstract: | The knowledge of the dielectric properties of materials, for the design of several components and circuits at high frequencies, is mandatory. In this paper, we present a simple method for the estimation of the dissipation factor (loss tangent) of dielectric materials based on the reflection measurement of a single microstrip line, which is applied to some common known materials, such as FR-4 and Rogers RO3010 laminates. The obtained results match well with the data on the literature for the considered materials. |
| Author(s): | R. Goncalves, R. Magueta, P. Pinho, N. B. Carvalho |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 903 KB |
| Title: | Improvements in DNA Biosensors Using Joint Split Ring Resonators Coupled with Thin Film Microstrip Line |
| Abstract: | Detecting the presence of materials in biomedical science using THz sensors, especially thin DNA strands, needs considerably sensitive sensors. Connection of unit cells in new frequency selective surface (FSS) structure, coupled with transmission line is introduced so that not only helps to miniaturize in sensing applications through THz frequency range, but also has steeper flanks in transitions, thus leads us to have higher sensitivities. All of the results are taken out from resonant frequencies related to reflection (s11), a new property used instead of transmission loss (s21), which is measurable using THz spectrometers. The effect of analyte thickness and dielectric properties of load on frequency response is explained. This approach is a new way in recognizing very small amounts of material even with rather low dielectric constants. |
| Author(s): | M. Abdolrazzaghi, A. Abdolali, S. Hashemy |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 518 KB |
| Title: | New Compact Dual Bandpass Filter Using Coupled Double-Ring Resonators and DGS-Technique |
| Abstract: | This paper presents a design of dual-band bandpass filter using novel ring resonator and H-defected ground. The bandpass filter is designed optimized and realized using mixed coupled microstrip double ring resonators and two electrically coupled H-cells DGS resonators, which are etched in background of the structure. Using this new ring structure leads to generate a selective bandpass filter with two isolated passbands. The measurement results show that the optimized filter has two passbands, the first band from 1.6 GHz to 2 GHz and the other from 3.6 GHz to 5.5 GHz. The proposed structure occupies an area of (0.45?g × 0.35?g) with ?g = 0.044 m. The simulated and experimented results show good agreement and validate the proposed approach |
| Author(s): | A. Boutejdar, N. M. Eltabit, A. A. Ibrahim, E. P. Burte, M. A. Abdalla |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 470 KB |
| Title: | Resonant and Radiation Characteristics of Rectangular Microstrip Patch Antenna on Suspended-Composite Substrates |
| Abstract: | In this paper, the resonance and radiation characteristics of rectangular microstrip patch printed on suspended and composite substrates are investigated theoretically. The analysis approach is based on the spectral-domain method of moments in conjunction with the stationary phase method. The complex resonant frequency of the microstrip antenna on suspended and composite substrates is studied with sinusoidal functions as basis functions, which show fast numerical convergence. Using a matrix representation of each layer, the far-field pattern of the suspended-composite configuration is efficiently determined by the (TM, TE) representation. The validity of the solution is tested by comparison of the computed results with experimental data. Finally, numerical results for the effects of suspended and composite substrates on the resonant frequency and half-power bandwidth are also presented. |
| Author(s): | S. Bedra, T. Fortaki |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 763 KB |
| Title: | Combined PSO-FDFD Optimization of Rectangular Ridged Waveguides |
| Abstract: | Finite-difference frequency-domain technique in conjunction with the particle swarm optimization algorithm is presented as an effective procedure for ridged waveguides design optimization. A suitable objective function is furthermore able to deal with the conflicting requirements of wide bandwidth and high power handling capability. Different configurations have been analyzed, and the influence of the algorithm parameters on the optimized structure has been investigated. |
| Author(s): | M. Simone, A. Fanti, G. Montisci, G. A. Casula, G. Mazzarella |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 524 KB |
| Title: | Narrow-band Bandpass Filters with Improved Upper Stopband Using Open/Shorted Coupled Lines |
| Abstract: | Two transversal narrow-band bandpass filters with improved stopband based on open/shorted coupled lines and transversal signal-interaction concepts are proposed in this paper. By utilizing the stopband transmission characteristic of the open/shorted coupled lines, three transmission zeros can be easily achieved to suppress the second harmonic for the first bandpass filter. To further reduce the circuit size of the first filter, unequal open stubs and transmission lines are used for the second bandpass filter with six transmission zeros in the upper stopband. The transmission zeros near the passband can be adjusted conveniently by only changing the electrical length of the open/shorted stubs when the ratio of characteristic impedance is fixed. To verify the presented concepts, two prototypes (?r =2.65, h = 0.508 mm, tan? = 0.003) with 3-dB fractional bandwidths (FBWs) of 4.3% (1.78-1.86 GHz), 2.8% (1.76-1.81 GHz) are designed and fabricated. Good agreements are observed for the theoretical and measured results, indicating good in-band filtering performances and high selectivity. |
| Author(s): | W. Feng, M. Hong, W. Che |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1174 KB |
| Title: | A New Design of Very Compact UWB Band-Stop Filter Using Coupled W-Shaped Strips |
| Abstract: | In this paper, a compact microstrip bandstop filter (BSF) with 3-18 GHz bandwidth for radar applications is proposed. The microstrip filter configuration consists of a transmission line with a pair of coupled W-shaped strips as a stub, and a ground plane. Operation frequencies of the filter can be easily controlled by changing the size of W-shaped strips. The proposed band-stop filter has a very wide bandwidth from 3 to 18 GHz that can be used in C-band (4-8 GHz), X-band (8-12 GHz) and Ku-band (12-18 GHz) applications. An excellent agreement between measured and simulated was obtained. 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 mm2 . The proposed antenna configuration is simple, easy to fabricate and can be integrated into any radar system. |
| Author(s): | H. Akbarzadeh, N. Ojaroudi, Y. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 639 KB |
| Title: | Electromagnetic Beam Position Monitoring Model for Particle Energy Linear Accelerator |
| Abstract: | Beam position monitoring (BPM) systems are crucial in particle acceleration facilities such as linear and circular accelerators. They are used to maintain a stable and precise beam position to achieve a high level of beam quality. BPMs are also essential for accelerator commissioning, performance optimisation, and fault analysis. Beam functional properties information, such as displacement from the desired axis, information about synchrotron oscillations and betatron movements can be derived from data gathered in BPM systems. Medical linear accelerators (linacs) also employ beam position measurements to ensure optimal generation of treatment radiation. The most common form of analysis is to use a multi-physics based approach and model the beam as a stream of electrons, often involving Monte Carlo implementation – an accurate but computationally expensive approach. This paper presents a simple, but robust and efficient, CST microwave model of the linear accelerator (linac) beam, generated using a simplified approach to beam modeling that uses a conducting filament in place of the particle. This approach is validated by comparison with published work. An approach to BPM using the method applied in this paper opens up opportunities to further analyze the overall design and that of components of particle accelerator systems using commonly available full-wave electromagnetic simulators without the need to include specific particle solutions. |
| Author(s): | S. Hussain, A. Duffy, H. Sasse |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 682 KB |
| Title: | Design and Electromagnetic Analysis of a New Rotary-Linear Switched Reluctance Motor in Static Mode |
| Abstract: | A newly designed rotary-linear switched reluctance (RLSRM) motor is presented and electromagnetically analyzed in this paper. The motor has an integrated structure and can control both linear and rotary motions. It is mainly designed to control the engagement of a rotating gear. For this purpose a twosection motor comprised of a rotary and a linear SRM is designed. In the middle part of the motor assembly, a three-phase rotary SRM with 6 stator and 4 rotor poles creates rotary motion. The linear section which is a transverse flux two-phase SRM is composed of two parts placing at each side of the rotary section. The cylindrical translators inside the linear stator poles provide short magnetic flux paths which reduce the core losses and increase the force per volume. The motor parameters derived from the motor design procedure are evaluated using 3-dimensional finite element analysis (3DFEA). The motor performance indices such as flux linkages, flux density, mutual flux, static torque and force for various loads are obtained and assessed for rotary and linear motions. Finally, a comparative study is performed and 3DFEA results are compared with two different RLSRM structures. The comparison shows that the proposed structure has the highest force per motor volume. |
| Author(s): | M. M. Nezamabadi, E. Afjei, H. Torkaman |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1165 KB |
| Title: | Design and Non-Linear Modeling of a Wide Tuning Range Four-Plate MEMS Varactor with High Q-Factor for RF Application |
| Abstract: | In this study, a micro-electromechanical variable capacitor that can achieve a wide tuning range is presented. The mechanical behaviors such as squeezed film damping and modal analysis are investigated. Also, scattering parameters, electromagnetic properties, and linear and nonlinear circuit models are presented for MEMS varactors. The four-plate tunable capacitor has nominal capacitance of 0.055 pF, a Q-factor of 175 at 10 GHz, and a tuning range of 2.59:1. The presented fourplate MEMS varactor has a suspended plate with the ability of moving downward and upward in order to increase the tuning range. The results were obtained by using simulation software. For the mechanical analyses, FEM in COMSOL Multiphysics software was used, and Ansoft HFSS and Agilent ADS were used for the electromagnetic analyses. |
| Author(s): | M. Moradi, R. S. Shirazi, A. Abdipour |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 932 KB |
| Title: | Characterization of Surface Cracks Using Eddy Current NDT Simulation by 3D-FEM and Inversion by Neural Network |
| Abstract: | In this work, we suggest an approach of signal inversion from sensors used in eddy current (EC) nondestructive testing (NDT). The aim is to characterize surface cracks from the EC signal. A methodology that combines 3D finite element (FEM) simulation and a data inversion by neural networks (NN) is proposed. We show that the use of a set of numerical measurements representing the EC signature of surface crack enables to remedy of the unicity problem. The obtained results show that the developed approach leads to the quantification of the crack. |
| Author(s): | B. Helifa, M. Feliachi, I. K. Lefkaier, F. Boubenider, A. Zaoui, N. Lagraa |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 596 KB |
| Title: | Nonlinear Modelling Approach for Linear Switched Reluctance Motor and its Validation by Two Dimensional FEA |
| Abstract: | This paper exposes two procedures in order to develop a refined analytical model which describes the behaviour of a linear switched reluctance motor. The first approach is based on the flux linkage and the second on the inductance, both versus position and current. Taking into account the non-linearity of the magnetic circuit, models are expressed by either Fourier series or polynomials where the only first three components are considered. Results of these analytical approaches are compared with those obtained using finite element methods (FEM) where a good agreement is observed. |
| Author(s): | I. Mahmoud, M. Fathallah, H. Rehaoulia |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 727 KB |
| Title: | Utilization of Protruded Strip Resonators to Design a Compact UWB Antenna with WiMAX and WLAN Notch Bands |
| Abstract: | In this paper, a new design of ultrawideband (UWB) microstrip monopole antenna is presented. The main novelty of the proposed structure is the using of protruded strips as resonators to design an UWB antenna with dual band-stop property. In the proposed design, by cutting the rectangular slot with a pair of rotated Y-shaped strips in the ground plane, additional resonance is excited and much wider impedance bandwidth can be achieved. To make a single band-notched function, the square radiating patch is converted to the square-ring structure with a pair of protruded fork-shaped strips. Finally, by cutting a rectangular slot with a protruded M-shaped strip at the feed line, a desired dual band-notched function is achieved. The measured results reveal that the presented dual band-notched antenna offers a very wide bandwidth from 2.8 to 11.6 GHz, with two notched bands, around of 3.3-3.7 GHz and 5-6 GHz covering all WiMAX and WLAN bands. |
| Author(s): | J. Mazloum, N. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 684 KB |