Ajalawit Chantaveerod

Iterative Solutions for Electromagnetic Fields at Perfectly Reflective and Transmissive Interfaces Using Clifford Algebra and the Multidimensional Cauchy Integral

A technique is presented for calculating the solution of Maxwells equations using a CFIE based on the Cauchy integral and formulated in the guise of Clifford algebra. This formulation has a geometric interpretation leading to an iterative method of solution which is easily proven as convergent and correct for both perfectly reflective and perfectly transmissive interfaces. Simple test cases involving a cubic boundary and plane wave and dipole sources are used to investigate the numerical performance of the method.

Numerical Computation of Electromagnetic Far-field from Near-Field using Integral Equation based on Clifford Algebra

In this paper, it is proposed to compute the full far-field from the full near-field data by using integral equation based on Clifford algebras. This method can be used to solve directly the Maxwells equation based on Clifford algebras (Dirac equation) since the key tool is the fundamental solution of them. The formulation of this method is structured in the form Clifford arithmetic and the results appear in the form of Clifford numbers. However, the results are decoded into the electric and magnetic fields in order to compare directly with known analytical results.

An EM scattering algorithm for all materials

A simple iterative algorithm is presented for the calculation of the electromagnetic radiation scattered from objects of arbitrary shape made from either lossless or lossy dielectrics or conductors. Convergence of the algorithm is tested on materials of all such types. It is found that the algorithm converges for all materials; faster for lossy ones.

Design of a Magneto - Electric Dipole Antenna for FM Radio Broadcasting Base Station Antenna Implementation

This work presents the design of a magneto-electric dipole (MED) antenna for the base station antenna of FM radio broadcasting implementation. The advantages of MED antenna are high gain, stable and symmetrical radiation patterns in both electric and magnetic planes, and low back lobe radiation pattern. The antenna was designed and studied to achieve the optimal dimensions of configuration parameters. The prototype antenna was fabricated and measured to validate its S11, radiation patterns, and gain. The impedance bandwidth was 33.49%, and the average gain was 7.78 dBi at the entire operating frequency (88–108 MHz). The measured results are in good agreement with the simulated ones.

Accurate evaluation of weakly singular integral in combined field integral equation on clifford algebra with numerical integration

In this paper, the formulation of multi-dimensional Cauchy integral equation, which is in an integral form of Maxwells equations, is presented on Clifford algebra to increase the accuracy of numerical solutions. The advantage of this formulation is the kernel integral concerning without the strongly singular function. To obtain the solution of the Cauchy integral equation, the boundary element technique is exploited to numerically solve with the quadrilateral function via Gauss-Quadrature technique. The accuracy of the obtained fields is investigated by comparing with those from the known analytical method.

Parallel computation of iterative solution for electromagnetic fields using Clifford algebra and the multidimensional Cauchy integral

Design of a parallel computation of iterative solution for electromagnetic fields formulation obtained from the multidimensional Cauchy integral equations based on Clifford algebra on a multi-computer system is presented. The presented parallel algorithm enhances the Cauchy integral equations whose kernel of integration is simple and contains weakly singular integral by saving time consuming and increasing the memory capacity in the calculation. To implement and demonstrate the computation, the domain decomposition techniques and the Message Passing Interface (MPI) programming are respectively exploited. The performance of the presented algorithm is investigated in two aspects: the speed and the efficiency of calculation. The speed linearly increases as a number of processors are added while the efficiency is always near 1.0.

Application of Cauchy integral equation on Clifford algebra for forward-backward wave decomposition

A novel decomposition technique of the forward and backward propagating waves is presented. This technique exploits the Cauchy integral equation based on Clifford algebra application which the integral operators satisfying with Maxwells equations provide all components of electromagnetic fields along the boundary of the problem. It is able to solve the boundary value problem in the case of partial transmission and reflection. The presented technique is implemented with the boundary element method to verify the performance by decomposing the summation of forward and backward propagating waves of a sample boundary whose shape is a cube. These recovered fields on continuous (flat) and discontinuous (edge and corner) surfaces are more accurate when increase the number of elements. The measured error is about 0.02%-0.3% at wavenumber k = 1.0Rad/m.