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The purpose of this study is the formulation of an efficient method to compute and analyse the scattering characteristics of cracks or grooves in a conducting object, where the size of the crack is significantly larger than the wavelength of an incident plane wave.

A hybrid finite element-boundary element procedure is formulated for the computation of the scattering properties of the object, where the fast multipole method is used in the boundary integral formulation. The basic fast multipole procedure is enhanced by utilising a fast Fourier transform-based convolution algorithm for the computation of the interactions between groups of source and field elements.

The algorithm accelerates the evaluation of the group interactions and enables the reduction of the memory requirements without introducing an additional approximation into the procedure.

The fast multipole method with convolution algorithm shows to be more efficient for the computation of scattering problems with a large number of unknowns than the conventional procedure.

The computation of 3‐D eddy current problems is an important topic both in theoretical and engineering areas. Based on Green's theorem, Kost theoretically developed a BEM formulation for general 3‐D nonlinear eddy current problems. The parallel implementation of this formulation in the linear case has been made on a massively parallel supercomputer, where a constant triangular element was used.

The calculation of magnetic shielding with ferromagnetic material by an effective reluctivity method and a time step method based on the finite element calculation is investigated. The calculation results of both methods are compared with measurement results and with each other in order to check their reliability and accuracy. It turns out that both methods give similar results for the field inside the shielding material, whereas in the surrounding air the effective reluctivity method gives more accurate results than the present time step method.

Accuracy and time consumption in numerical computations are often in contradiction to each other. In modern industrial design processes flux field computation becomes more and more important. Thus, it is desirable to minimize any methodical error for better performance. This paper discusses a flaw of frequently used standard elements in boundary‐element‐method and shows a way to avoid it.

The purpose of this paper is the analysis of the radiation and impedance characteristics of cavity backed patch antennas embedded in a curved surface. Single patch elements and small scale array antennas are considered. The impact of curvature on the performance of the patch antenna is investigated, and the effect of mutual coupling between the elements in an array is examined.

A finite element‐boundary integral procedure has been implemented to accurately determine the performance characteristics of the patch radiators on planar and cylindrical surfaces. Simulated results will be shown to be in good agreement with measurements.

Mutual coupling effects between array elements are examined and it can be observed that an active element primarily interacts with the nearest neighbour elements. A comparison of an array element with a single patch radiator shows that the mutual coupling effects cause no significant mismatch between a patch and a feed network in practical applications.

The characteristics of conformal microstrip antennas are investigated for single patch radiators and patch elements in array environments. Simulations are supported by measurements.

This paper presents the use of transmission‐line modelling ‐ time domain (TLM‐TD) method to analyse the fields in mode stirred reverberation chambers excited by wires. It will be shown how the fields inside the chamber are distributed for a large range of excited frequencies. The work intends to develop a numerical procedure to verify the effectiveness and usefulness of the TLM method to electromagnetic compatibility problems. The numerical model presented here is based on the classical symmetrical condensed 3D node. The simulations will be compared with method of moments results obtained in available benchmark data. Some comments are made on comparisons between the two techniques.