Use of the Simultaneous Diagonalization Technique in the Ax=lBx Eigenproblem Applied to the Computation of the Characteristic Modes
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Use of the Simultaneous Diagonalization Technique in the Ax=lBx Eigenproblem Applied to the Computation of the Characteristic ModesAbstract
Characteristic modes developed by Garbacz, Harrington and Mautz have long been used in the analysis of radiation and scattering from conducting bodies and apertures. For their computation, it is necessary to solve an eigensystem of the form Ax=lBx. If the matrices (A,B) are Hermitian and B is positive definite, the generalized eigenvalue problem can be accurately solved using the simultaneous diagonalization technique (SDT). Because of numerical approximations and rounding sometimes it may happen that the matrices properties deteriorate and the SDT procedure becomes inapplicable. In this work a new technique, developed recently by Higham and Cheng is proposed as a method to solve these deteriorate cases. It is applied to the computation of the characteristic modes for some scattering problems. Results are analyzed and discussed.
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20579 0.20572 14.8938+76.7077j
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