ACES Publication Search
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| Title: | ACES September 2010 Full Journal |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 5930 KB |
| Title: | ACES September 2010 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 473 KB |
| Title: | The Joy of Computing with Volume Integrals: Foundations for Nondestructive Evaluation of Planar Layered Media |
| Abstract: | As an alternative to the finitedifference time-domain (FDTD), the finiteelement method (FEM), and the method of moments (MoM) based on the surface integral equation (SIE), a volume-integral equation (VIE) approach using the method of moments and conjugate-gradient methods is presented to address a wide variety of complex problems in computational electromagnetics. A formulation of the volume integral method is presented to efficiently address inhomogeneous regions in multi-layered media. Since volume element discretization is limited to local inhomogeneous regions, numerical solutions for many complex problems can be achieved more efficiently than FDTD, FEM, and MoM/SIE. This is the first of a series of papers dealing with volume-integral equations; in subsequent papers of this series we will apply volume-integrals to problems in the field on nondestructive evaluation. |
| Author(s): | H. A. Sabbagh, R. K. Murphy, E. H. Sabbagh, J. C. Aldrin, J. S. Knopp, M. P. Blodgett |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 837 KB |
| Title: | The Joy of Computing with Volume Integrals: Validation and Performance Comparison |
| Abstract: | This is the second paper in a series dealing with the application of computational electromagnetics to nondestructive evaluation, using the vehicle of volume-integral equations, as developed in the preceding paper in this volume. A challenge-problem in the field of nondestructive evaluation is the inspection of fastener sites for fatigue cracks in multilayer structures. Using the volume-integral equation approach, problems comprising multilayer structures, ferromagnetic fastener sites, gaps between materials interfaces, and the presence of fatigue cracks are accurately modeled. Simulated studies are presented with VIC-3D©, a proprietary volume-integral code, and comparisons are made with FEM highlighting performance advantages of the VIE approach. Further, the role that volume-integral equations play in the context of other well-known computational-electromagnetic algorithms is discussed. |
| Author(s): | H. A. Sabbagh, R. K. Murphy, E. H. Sabbagh, J. C. Aldrin, J. S. Knopp, M. P. Blodgett |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 1979 KB |
| Title: | Stable Partial Inductance Calculation for Partial Element Equivalent Circuit Modeling |
| Abstract: | Accurate and stable analytical solutions for partial element calculation in partial element equivalent circuit (PEEC) modeling are desirable due to fast and simple usage. Conventional analytical formulae based on integral Neumann formula may give miscalculations when we compute the partial inductance of three-dimensional structures with large spacing. In this paper, a novel model-order reduction (MOR) method is presented for mutual inductance calculation in order to improve its accuracy and stability. Mutual inductances of higher order models are represented by relatively lower order models. The criteria for MOR are revealed and a code implementation routine is described. The numerical accuracy, stability and calculation cost are investigated comparing with conventional procedures. Numerical experiments show that the MOR method can guarantee numerical stability and reduce calculation complexity simultaneously, and it has advantages to be implemented in PEEC modeling for large complex electronic systems. |
| Author(s): | Z. Song, F. Duval, D. Su, A. Louis |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 919 KB |
| Title: | Complex Incomplete Cholesky Factorization Preconditioned Bi-conjugate Gradient Method |
| Abstract: | Linear systems generated by finite element method (FEM) always have a symmetrical sparse system matrix, which requires a large amount of computation and memory effort to access its zero elements. To address this problem, a fully-sparse storing scheme is proposed to store only nonzero symmetrical elements of the sparse system matrix. Meanwhile, for some illconditioned system matrixes, conventional iterative solution methods may incur such problems as slow convergence and even failure of convergence. To solve this problem, we further develop a fast convergent preconditioned biconjugate gradient method (PBCG) based on a real incomplete Cholesky factorization preconditioner. Numerical experiments show that the proposed method accelerates the convergence and is applicable for the large-scale complex linear systems. |
| Author(s): | Y. J. Zhang, Q. Sun |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 295 KB |
| Title: | Efficient Analysis Technique for Modeling Periodic Structures Based on Finite Element Method using High-Order Multiscalets Functions |
| Abstract: | Periodic structures have a variety of important applications in electromagnetic engineering and modern technologies. Commonly used, periodic structures include frequency selective surfaces, optical gratings, phased array antennas and various metamaterials. A three-dimensional finite element method (FEM) with efficient boundaries conditions is presented to simulate the electromagnetic properties of homogeneous periodic material. In our approach, we describe an accurate and efficient numerical analysis based on high-order multiscalets applied in vector edge FEM using new reduction meshing technique (MSRM-FEM) to characterize the electromagnetic properties of periodic structures. Here, we have achieved a factor of 4 in memory reduction and 7?11 in CPU speedup over the typical meshing. The FEM is applied to solve Maxwell’s equation in the unit cell. The Floquet’s theorem is used to take into account the periodicity of the boundaries conditions radiation for the unit cell. The numerical results are compared to published data and other simulation results. Good agreement is important to establish the validity and usefulness of the (MSRM-FEM) method given in this paper. |
| Author(s): | A. B. Ali, E. A. Hajlaoui, A. Gharsallah |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 500 KB |
| Title: | Equivalent Circuits for Nonuniform Transmission Line Simulation |
| Abstract: | The hereby article is devoted to elaboration of the analysis method of nonuniform transmission line (NUTL) with utilization of typical circuit simulator like SPICE. It is assumed that quasi-TEM modes are propagated in the NUTL. Solution of the problem is divided into three parts. 1) The analysis of nonuniform transmission line is reduced to the analysis of cascaded sections of linear varied nonuniform transmission line (LNTL). Proper algorithm originates from literature. 2) Computational model of linear varied nonuniform transmission line is elaborated following the asymptotic waveform evaluation methodology. The q-pole model is matched to imitate position of zeros and poles of admittance matrix of the NUTL. 3) Synthesis of passive circuit which implements the model for broad range values of LNTL slope constant. Consequently parameters of the circuit can be evaluated precisely as polynomial function of slope constant. Resultant model can be easily written in SPICE simulation language. |
| Author(s): | J. Izydorczyk |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 795 KB |
| Title: | High-Isolation and Low-Loss RF MEMS Shunt Switches |
| Abstract: | This paper presents the design and simulation of a radio frequency (RF) microelectromechanical system (MEMS) shunt switch using a three-dimensional RF simulator, Em3ds10 (2008 version) software for the frequency range of 1-40 GHz. The shunt capacitive switch is electrostatic actuated and designed with a meander beam support to lower the pull-in voltage. Fast simulations of complex structures based on a method-of-moment approach allow for optimal design of MEMS switch. The switch has a simulated pull-in voltage of 2.5 V and the RF performances of insertion loss and isolation are less than -0.2 dB and -50 dB at 12 GHz, respectively. |
| Author(s): | H. Jaafar, O. Sidek, A. Miskam, R. Abdul-Rahman |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 368 KB |
| Title: | A New UWB Slot Antenna with Rejection of WiMax and WLAN Bands |
| Abstract: | This paper presents a compact coplanar waveguide (CPW) fed ultra wideband (UWB) planar slot antenna with the characteristics of dual band rejection. The antenna consists of a rectangular slot with triangular tuning stub. The band notching of WiMax (3.2-3.8 GHz, with VSWR 68 at 3.5 GHz) is achieved by inserting a ‘U’ slot in the ground plane and band-notching of WLAN 802.11a (5.1-5.9 GHz, with VSWR 14 at 5.5 GHz) is obtained by embedding a ‘U’ type slot in the triangular tuning stub. The characteristics of the proposed antenna are studied both numerically and experimentally, and the design parameters for achieving optimal operation of the antennas are also analyzed extensively. The size of the antenna is around 28mm (L) × 21mm (W) × 1.6mm (T). The prototype of the proposed antenna is fabricated for its optimal values and tested. The VSWR, radiation pattern and gain are measured and agree well with the simulation results. The proposed antenna is simple, easy to fabricate and can be integrated into any UWB system, which can work without interference from WiMax, WLAN, and HYPERLAN/2 systems. |
| Author(s): | J. William, R. Nakkeeran |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 646 KB |
| Title: | Microstrip Inductor Design and Implementation |
| Abstract: | High frequency (HF) microstrip spiral inductor design using analytical formulation with network model and numerical simulation with planar electromagnetic simulator, Sonnet, are given for high power RF application. The simplified lumped element equivalent network model parameters for the spiral inductor are used to obtain the initial dimensions of the spiral inductor for simulation. The spiral inductor is then simulated with planar electromagnetic simulator, Sonnet, using the geometry constructed with the physical dimensions obtained from the network model for the desired inductance value. The parametric study of the spiral inductor is conducted to investigate the variation on its quality factor, self resonance frequency and inductance value. The spiral inductor is implemented on a ceramic substrate and measured. The measurement, simulation, and analytical results are found to be close. |
| Author(s): | A. Eroglu |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 418 KB |
| Title: | Analysis of Dual-Mode Microstrip Patch Filter using Multiscale Wave Concept Iterative Process |
| Abstract: | An iterative method based on the multiscale approach named multiscale wave concept iterative process (MWCIP) is introduced in this paper. This new approach is an extension of the known wave concept iterative process (WCIP). The specificity of the MWCIP method is the nonuniform meshing with macropixels used to improve the time delay computations of the classical iterative procedure. The method is applied successfully to a nondegenerate dual-mode microstrip patch filter. Comparison between the new and classical iterative methods shows that with the presented approach the CPU time and memory requirement have been considerably reduced. |
| Author(s): | T. I. E. Brahim, H. Zairi, A. Gharsallah, A. Gharbi, H. Baudrand |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 488 KB |