A new boundary integral approach to the determination of the resonant modes of arbitrarily shaped cavities

• Published in: IEEE transactions on microwave theory and techniques 1995-08, Vol.43 (8), p.1848-1856
• Main Authors: Arcioni, P., Bressan, M., Perregrini, L.
• Format: Article
• Language: English
• Subjects: Acceleration; Cavity resonators; Classical and quantum physics: mechanics and fields; Classical electromagnetism, maxwell equations; Classical field theories; Eigenvalues and eigenfunctions; Electromagnetic analysis; Exact sciences and technology; Integral equations; Magnetic resonance; Message-oriented middleware; Physics; Resonant frequency; Transmission line matrix methods; Waveguide junctions
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/22.402270

We present an efficient algorithm to determine the resonant frequencies and the normalized modal fields of arbitrarily shaped cavity resonators filled with a lossless, isotropic, and homogeneous medium. The algorithm is based on the boundary integral method (BIM). The unknown current flowing on the cavity wall is considered inside a spherical resonator, rather than in free-space, as it is usual in the standard BIM. The electric field is expressed using the Green's function of the spherical resonator, approximated by a real rational function of the frequency. Consequently, the discretized problem can be cast into the form of a real matrix linear eigenvalue problem, whose eigenvalues and eigenvectors yield the resonant frequencies and the associated modal currents. Since the algorithm does not require any frequency-by-frequency recalculation of the system matrices, computing time is much shorter than in the standard BIM, especially when many resonances must be found.< >