An Improvement of Global Complex Roots and Poles Finding Algorithm for Propagation and Radiation Problems

An improvement of the recently developed global roots finding algorithm has been proposed. The modification allows to shorten the computational time by reducing the number of function calls. Moreover, both versions of the algorithms (standard and modified) have been tested for numerically defined functions obtained from spectral domain approach and field matching method. The tests have been performed for three simple microwave structures (open waveguides and conformal antenna resonator). The results have been verified and the increase of efficiency for the improved version of the algorithm has been confirmed.

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