ScholarBank@NUShttps://scholarbank.nus.edu.sgThe DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.Sat, 30 Sep 2023 11:11:07 GMT2023-09-30T11:11:07Z5091- Solving mixed dielectric/conducting scattering problem using adaptive integral methodhttps://scholarbank.nus.edu.sg/handle/10635/57444Title: Solving mixed dielectric/conducting scattering problem using adaptive integral method
Authors: Ewe, W.-B.; Li, L.-W.; Leong, M.-S.
Abstract: This paper presents the adaptive integral method (AIM) utilized to solve scattering problem of mixed dielectric/conducting objects. The scattering problem is formulated using the Poggio-Miller- Chang-Harrington-Wu-Tsai (PMCHWT) formulation and the electric field integral equation approach for the dielectric and conducting bodies, respectively. The integral equations solved using these approaches can eliminate the interior resonance of dielectric bodies and produce accurate results. The method of moments (MoM) is applied to discretize the integral equations and the resultant matrix system is solved by an iterative solver. The AIM is used then to reduce the memory requirement for storage and to speed up the matrix-vector multiplication in the iterative solver. Numerical results are finally presented to demonstrate the accuracy and efficiency of the technique.
Thu, 01 Jan 2004 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/574442004-01-01T00:00:00Z
- Adaptive integral method for electromagnetic scattering and antenna radiationhttps://scholarbank.nus.edu.sg/handle/10635/69182Title: Adaptive integral method for electromagnetic scattering and antenna radiation
Authors: Li, L.-W.; Ewe, W.-B.; Chang, C.-S.
Abstract: This paper presents an efficient and fast solver developed based on the adaptive integral method and its application for characterizing electromagnetic scattering by arbitrarily shaped objects, and designing antennas for large scaled radio radiation problems. Although a brief summary of the historical development will be given, the emphasis of the paper will be given to the recent advances and new developments made quite recently. During the development procedure, the method of moments (MoM) has been considered and applied as a foundation to start with for discretizing the integral equations. The resultant matrix system of a large dimension is then solved by an iterative solver where the adaptive integral method (AIM) is employed on the top of them to accelerate the matrix-vector multiplications and to reduce matrix storage. Various numerical results are presented to demonstrate the accuracy, efficiency, and applicability of the technique. © 2005 IEEE.
Sat, 01 Jan 2005 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/691822005-01-01T00:00:00Z
- Preconditioners for adaptive integral method implementationhttps://scholarbank.nus.edu.sg/handle/10635/57108Title: Preconditioners for adaptive integral method implementation
Authors: Ewe, W.-B.; Li, L.-W.; Wu, Q.; Leong, M.-S.
Abstract: The performance of three preconditioners, namely, diagonal, block-diagonal, and incomplete lower-upper preconditioners, are investigated in this communication for increasing the efficiency of iterative solvers in adaptive integral method implementation. These preconditioners are implemented to accelerate the solution of electromagnetic scattering problems in a comparative study. Numerical results have shown some improvements in convergence rate, when these preconditioners are employed. © 2005 IEEE.
Fri, 01 Jul 2005 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/571082005-07-01T00:00:00Z
- Fast solution of mixed dielectric/conducting scattering problem using volume-surface adaptive integral methodhttps://scholarbank.nus.edu.sg/handle/10635/56020Title: Fast solution of mixed dielectric/conducting scattering problem using volume-surface adaptive integral method
Authors: Ewe, W.-B.; Li, L.-W.; Leong, M.-S.
Abstract: This paper presents the adaptive integral method utilized to solve scattering problems of mixed dielectric and conducting objects using volume-surface integral equation. The scattering problem is formulated using volume integral equation and surface integral equation for dielectric material object and conducting object, respectively. The combined field integral equation is formulated to treat closed conducting surfaces. The method of moments is applied to discretize the integral equations. The resultant matrix system is solved by an iterative solver where the adaptive integral method is employed to accelerate the matrix-vector multiplication. The block diagonal preconditioner is implemented to further accelerate the convergence of the present solution. Numerical results are presented to demonstrate the accuracy and efficiency of the technique. © 2004 IEEE.
Mon, 01 Nov 2004 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/560202004-11-01T00:00:00Z
- Analysis of reflector and horn antennas using adaptive integral methodhttps://scholarbank.nus.edu.sg/handle/10635/69403Title: Analysis of reflector and horn antennas using adaptive integral method
Authors: Ewe, W.-B.; Li, L.-W.; Wu, Q.; Leong, M.S.
Abstract: This paper presents an analysis of electrically large antennas using the adaptive integral method (AIM). The arbitrarily shaped perfectly conducting surfaces are modeled using triangular patches and the associated electric field integral equation (EFIE) is solved for computing the radiation patterns of these antennas. The method of moments (MoM) is used to discretize the integral equations and the resultant matrix system will be solved by an iterative solver. The AIM is employed in the iterative solver to speed up the matrix-vector multiplication and to reduce the memory requirement. As specific applications, radiation patterns of parabolic reflectors and X-band horns are computed using the proposed method. Copyright © 2005 The Institute of Electronics, Information and Communication Engineers.
Wed, 01 Jun 2005 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/694032005-06-01T00:00:00Z
- AIM analysis of scattering and radiation by arbitrary surface-wire configurationshttps://scholarbank.nus.edu.sg/handle/10635/54959Title: AIM analysis of scattering and radiation by arbitrary surface-wire configurations
Authors: Ewe, W.-B.; Li, L.-W.; Chang, C.-S.; Xu, J.-P.
Abstract: The adaptive integral method is utilized to solve electromagnetic scattering and radiation problems of conducting surface-wire configurations. The method of moments (MoM) is applied to establish the integral equations where triangular type basis functions are used to represent the currents on surfaces and wires. Attachment mode has been used to model the surface-wire junction to ensure the current continuity. The resultant matrix system is then solved by an iterative solver where the adaptive integral method (AIM) is employed to reduce memory requirements and to accelerate the matrix-vector multiplications. Numerical results are presented to demonstrate the accuracy and efficiency of the present technique for the arbitrary surface-wire configurations. © 2007 IEEE.
Mon, 01 Jan 2007 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/549592007-01-01T00:00:00Z
- AIM solution to electromagnetic scattering using parametric geometryhttps://scholarbank.nus.edu.sg/handle/10635/54960Title: AIM solution to electromagnetic scattering using parametric geometry
Authors: Ewe, W.-B.; Li, L.-W.; Wu, Q.; Leong, M.-S.
Abstract: This paper presents the adaptive integral method (AIM) utilized to solve electromagnetic scattering problems of an arbitrarily shaped conducting body with parametric geometry. The combined field integral equation is used to characterize the scattering problems of a closed conducting body whose surfaces are modeled using curvilinear patches. The formulated integral equations are then discretized and converted to a matrix equation using the method of moments. The resultant matrix equation is then solved by an iterative solver and the AIM is employed to accelerate the matrix-vector multiplication. Numerical results are presented to demonstrate the efficiency of the technique. © 2005 IEEE.
Sat, 01 Jan 2005 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/549602005-01-01T00:00:00Z
- AIM analysis of em scattering and radiation by arbitrary conducting surface-wire configurationshttps://scholarbank.nus.edu.sg/handle/10635/69252Title: AIM analysis of em scattering and radiation by arbitrary conducting surface-wire configurations
Authors: Ewe, W.-B.; Li, L.-W.; Chang, C.-S.
Abstract: In this paper, the adaptive integral method (AIM) is used to analyze the scattering and radiation by arbitrary conducting surface/wire configuration. The scattering problem is characterized using electric field integral equation and is solved by the method of moments (MoM). The AIM is implemented in the iterative solver to accelerate the matrix-vector multiplication and to reduce the memory requirement for the matrix storage. © 2005 IEEE.
Sat, 01 Jan 2005 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/692522005-01-01T00:00:00Z
- A compact wideband hybrid dielectric resonator antennahttps://scholarbank.nus.edu.sg/handle/10635/53961Title: A compact wideband hybrid dielectric resonator antenna
Authors: Gao, Y.; Ooi, B.-L.; Ewe, W.-B.; Popov, A.P.
Abstract: A novel wideband hybrid dielectric resonator antenna structure comprises a rectangular dielectric resonator (DR) and a coplanar waveguide (CPW) inductive slot is proposed. In this configuration, the CPW inductive slot simultaneously acts as an effective radiator and the feeding structure of the DR. Dual resonances of the two radiators are merged to extend the antenna's bandwidth. A parametric study is performed to optimize the antenna performance and a prototype for 5-GHz WLAN application has been built and tested.© 2006 ieee.
Sat, 01 Apr 2006 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/539612006-04-01T00:00:00Z