摘要:

The small aperture coupling theory is improved by introducing the radiation reaction fields as part of the polarizing field acting on the aperture. The principles of power conservation and reciprocity are used to determine the dipole strengths for radiation on either side of the aperture with the aperture closed. The theory thus enables coupling between dis-similar regions to be treated in a straightforward manner. The theory leads to physically meaningful equivalent circuits for describing small aperture coupling. Cavity coupling and radiation into free space are treated as examples.

ISSN:0272-6343    

DOI:10.1080/02726348208915154

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

A solution is presented for the calculation of mutual coupling between elements in a finite planar rectangular waveguide antenna array. The aperture dimensions can be less than the feeding, waveguide dimensions and the elements are uniformly spaced in each of two directions in either a rectangular or isosceles triangular lattice. The problem is formulated as an integral equation by requiring the transverse electric and magnetic fields to be continuous across the apertures. The integral equation is solved by the method of moments for the equivalent magnetic current in the aperture region. A single expansion function is used to approximate the electric field in each aperture. For apertures that are close together the normal quadruple half-space admittance integral is reduced to single integrals which are evaluated numerically. For apertures father apart, a double numerical integral solution is used. In addition, the symmetry property of the symmetric Toeplitz admittance matrix for the linear array case and the symmetric block-Toeplitz admittance matrix for the rectangular array case is utilized when solving for the unknown magnetic current coefficients.

ISSN:0272-6343    

DOI:10.1080/02726348208915155

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

ISSN:0272-6343    

DOI:10.1080/02726348208915156

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

A curve fitting and pole extraction algorithm has been developed and applied to exact frequency domain data for the surface fields on a perfectly conducting sphere. The data are fitted extremely closely, and for at least a handful of the lowest order SEM poles, the extracted poles and their residues are in good agreement with their known exact values. Unfortunately, this is not true if the frequency response is degraded in accuracy. In particular, noise effects are explored, and it is found that for noise levels typical of the best frequency domain experimental data it is no longer possible to locate more than (at most) the dominant SEM pole to a reasonable degree of accuracy.

ISSN:0272-6343    

DOI:10.1080/02726348208915157

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The paper presents a general reciprocity theorem which is valid for any couple of fields and scatterers ; especially, the surfaces of the scatterers in the two configurations may be different. The theorem is demonstrated from Maxwell equations in the sense of distributions, which permits one to take automatically into account the boundary conditions. Then, several classical relations are derived from the theorem, for two dimensional as well as three dimensional scatterers : classical reciprocity, optical theorem, relation between far scattered field and near field. Moreover, very simple expressions are found for the functional derivatives of the elements of the scattering matrices, which constitute powerful tools for the numerical solving of inverse scattering problems.

ISSN:0272-6343    

DOI:10.1080/02726348208915158

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor