ACES Publication Search
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| Title: | ACES April 2011 Full Journal |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 13224 KB |
| Title: | ACES April 2011 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 986 KB |
| Title: | Design of UWB Antennas to Monitor Cardiac Activity |
| Abstract: | This paper presents two novel ultra wideband (UWB) printed antennas designed to be part of a UWB radar system for cardiac activity monitoring. The two antennas have the same shape but differ in terms of dielectric substrate and dimensions and are designed to be used one in a wearable and the other in non-wearable (fixed) radar. With regard to the fixed antenna, numerical results show an optimum fidelity factor and an almost constant group delay in the 3.1 - 10.6 GHz frequency band. As concerns the wearable antenna, numerical results obtained considering the antenna placed in the vicinity of a box model of the thorax, containing a spherical model of the heart, show that small heart movements can be detected. Eventually, the two antennas have been realized and measured by means of a vector network analyzer finding a return loss lower than -10 dB in the 3.1 - 10.6 GHz frequency band with a good agreement between simulations and measurements. Also, measurements of the fixed antenna gain and radiation pattern, performed in an anechoic chamber, show a good agreement with simulations. |
| Author(s): | E. Pittella, P. Bernardi, M. Cavagnaro, S. Pisa, E. Piuzzi |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1000 KB |
| Title: | Computer Simulations of Microwave Heating with Coupled Electromagnetic, Thermal, and Kinetic Phenomena |
| Abstract: | A new functionality for the hybrid electromagnetic – thermodynamic simulations of microwave heating scenarios in the time domain is presented. The new functionality consists in the modelling of the heated load movement throughout the simulated process. Various types of the movement trajectories have been allowed for, including load rotation and load translation along user-defined piecewise-linear paths. Key aspects of this novel approach are addressed and justified from the computational electromagnetics perspective. Multiphysics simulation results are presented for a fictious and a commercially available microwave oven. |
| Author(s): | M. Celuch, M. Soltysiak, U. Erle |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1828 KB |
| Title: | Ultra High-Resolution FDTD Modeling of a High-Performance VLSI Package for Identifying Resonances and Coupling |
| Abstract: | It is becoming increasingly important to computationally predict, study, and prevent electromagnetic compatibility (EMC) issues arising within and between ICs and other components comprising portable electronic devices. Here, we conduct a phenomenological study involving an ultra high-resolution, threedimensional finite-difference time-domain (FDTD) model of a sample IC package having over one billion grid cells. Specifically, we determine the resonances and coupling patterns arising within the highly complex IC package. The frequency range of interest extends from 100 MHz to 7 GHz. Results indicate that the arrangement and geometry of the separate power, ground, and signaling networks comprising the IC package greatly influences the electromagnetic behavior within different regions of the package. |
| Author(s): | C. M. Ruiz, J. J. Simpson |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 2679 KB |
| Title: | Compact Antenna Designs for Wearable and Portable Medical System |
| Abstract: | A button wearable antenna and an Lshape planar inverted F antenna (PIFA) antenna were designed for medical eHealth system. A spiral top button wearable antenna was implemented into the antenna structure to obtain additional inductance. Both simulated and measured reflection coefficients show it can cover both the 2.4-2.5GHz and 5.15- 5.825 GHz ISM bands. Good omnidirectionality was achieved at x-y plane for all three bands. A compact L-shape PIFA antenna was designed and fabricated for laptop wireless local area network (WLAN) application to communicate with wearable antenna. The antenna was formed to L-shape to minimize the ground plane size, so that it can be fitted into the top corners of a laptop display. The effect of the presence of display panel was discussed. |
| Author(s): | W. Huang, A. A. Kishk |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1166 KB |
| Title: | Coupled Mode Analysis of Two-Dimensional Chiral Grating |
| Abstract: | This paper introduces a modal analysis for two-dimensional chiral grating. The grating structure is composed of rectangular chiral rods arranged in rectangular periodic cells and embedded in another chiral base material. Total fields are presented in terms of transverse electric and magnetic field components which are expanded as two sets of TE and TM Floquet modes. This representation is used in Maxwell’s curl equations to formulate the problem as an eigenvalue problem. The resulting eigenvalues correspond to the forward and backward propagation coefficients. On the other hand, the eigenvectors correspond to the amplitudes of the TE and TM Floquet modes in the forward and backward propagating modes. Reflection and transmission coefficients of two semi-infinite chiral gratings are obtained by combining this modal analysis and mode matching method. This analysis is extended to obtain the reflection and transmission coefficients of a finite thickness twodimensional chiral grating slab by using the generalized scattering matrix method. |
| Author(s): | A. M. Attiya |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 373 KB |
| Title: | A Novel Band-Stop Filter using Octagonal-Shaped Patterned Ground Structures along with Interdigital and Compensated Capacitors |
| Abstract: | This paper presents a novel compact microstrip band-stop filter (BSF) based on octagonal defected ground structure (DGS) along with interdigital and compensated capacitors. The proposed BSF has lower and higher cut-off frequencies of 3.4 GHz and 5.3 GHz, respectively. A comparison between simulation and measurement results confirms the validity of the BSF configuration and the design procedure. The compact filter occupies an area of (0.45?g × 0.35?g) with ?g = 0.044 m on an ?r = 3.66 substrate and shows a 44% bandwidth (? 2GHz) and a return loss of 0.1 dB. The experimental results show the excellent agreement with theoretical simulation results. |
| Author(s): | A. Boutejdar, M. Challal, A. Azrar |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1053 KB |
| Title: | Improvement of Transmission Line Matrix Method Algorithm Frequency Response Based on Modification of Cell Impedance |
| Abstract: | In this paper, an accurate and numerically robust singularity correction technique for the transmission line matrix method (TLM) algorithm is proposed. The impedance of the adjacent cells to the singularity is corrected by a scalar correction factor, which amounts to a quasi-static correction of the electric and magnetic energy stored in the TLM cells at the singularity. The effectiveness of this method in accurate modeling of structures with metallic strips (sharp edges) and 90 degree edge corners has been clearly validated against published measurement and common TLM simulation data. |
| Author(s): | M. Rajabi, N. Komjani |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 349 KB |
| Title: | Using Adaptive Cross Approximation for Efficient Calculation of Monostatic Scattering with Multiple Incident Angles |
| Abstract: | An adaptive cross approximation (ACA) based method is proposed for the fast analysis of the monostatic radar cross-section (RCS). Using the low-rank property, several largest eigenvalues and corresponding eigenvectors of the multiple right hand sides can be computed and saved efficiently by the ACA algorithm. The iterative solution of linear equations is required at these principle eigenvectors. Compared with solving linear equations at each angle repeatedly, the proposed method is able to greatly reduce the computation time. In order to efficiently solve the linear equations, the flexible general minimal residual (FGMRES) iterative solver is applied to compute the coefficients of Rao-Wilton-Glisson (RWG) basis functions. Numerical results demonstrate that the proposed method is efficient for monostatic RCS calculation with high accuracy. |
| Author(s): | Z. Liu, R. Chen, J. Chen, Z. Fan |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 2277 KB |
| Title: | Reduction of Mutual coupling in Microstrip Array Antenna using Polygonal Defected Ground Structure |
| Abstract: | The surface wave propagation is a significant problem in microstrip array antennas. Several methods have been reported to suppress the propagation of surface wave such as defected ground structure (DGS). The main problem in DGS is to determine the shape of ground slot. In this paper, a new method is proposed in which the slot is assumed to be a polygon and its shape is obtained by enhanced genetic algorithm (GA) and ant colony optimization (ACO) to have an array antenna with good gain and the least amount of return loss and mutual coupling. |
| Author(s): | A. Farahbakhsh, G. Moradi, S. Mohanna |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 877 KB |
| Title: | A DECOMPOSITION METHOD FOR THE ELECTROMAGNETIC SCATTERING FROM A CONDUCTIVE OBJECT BURIED IN A LOSSY MEDIUM |
| Abstract: | A new numerical solution method is presented for the electromagnetic field scattered by a perfectly conducting (PEC) cylindrical object with an arbitrary cross-section buried in a lossy dielectric half-space. The dielectric half-space is considered to be flat, and the method is outlined for TMz (horizontally) polarized incident wave. The surface equivalence principle and a decomposition method are utilized to form a set of electric field integral equations (EFIEs) for the currents on the object and the portion of the surface most strongly interacting with the object. To obtain the scattered electric field, the EFIEs are solved in the frequency domain using the method of moments (MoM). |
| Author(s): | S. Makal, A. Kizilay |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 898 KB |
| Title: | A New Ultra Wideband Fractal Monopole Antenna |
| Abstract: | Ultra wideband antennas are used greatly in commercial and military communication systems. A reduction in physical size and multiband capability are very important in the design of ultra wideband antennas. The use of fractal geometry in antenna design provides a good method for achieving the desired miniaturization and multi-band properties. In this paper, a compact, multi-band, and broad-band antenna based on new fractal geometry is designed, simulated, and measured. The proposed design is achieved by applying the 2nd iteration of a new fractal geometry to a wire monopole antenna. A numerical electromagnetics simulation is performed using SuperNEC electromagnetic simulator software. The results show that the proposed antenna can be used for 6 GHz – 30 GHz frequency range. Radiation patterns are also studied. |
| Author(s): | A. Azari |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1669 KB |
| Title: | Numerical Simulation of Substation Grounding Grids Buried in Vertical Earth Model Based on the Thin-Wire Approximation with Linear Basis Functions |
| Abstract: | In order to improve the precision of the numerical result, the fast convergent Galerkin's type of boundary element method (BEM) with one order basis function is developed to calculate the grounding system buried in the vertical multilayer earth model. In this paper, the method is taken to simulate and analyze a grounding system including a floating electrode with any complicated structure, which can be located anywhere in the vertical multilayer earth model. The quasi-static complex image method (QSCIM) and the closed form of Green's function for the vertical multilayer earth model are introduced; the QSCIM is implemented by the matrix pencil (MP) approach. |
| Author(s): | Z. Li, G. Li, J. Fan, Y. Yin |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 551 KB |