Efficient evaluation of antenna fields by a time-domain multipole analysis

[摘要] The contribution describes a systematic method to efficiently determine frequency-domainelectromagnetic antenna fields and characteristics for a broad spectrum via a single time-domain(e.g., Finite-Difference Time-Domain, FDTD) calculation. From a time-domain simulation of an antenna driven by awide-band signal, a single modified Fourier transformation yields the frequency-domainmultipole amplitudes. The corresponding multipole expansions are valid for the entire spectrum of theinput pulse and at any point outside a minimum sphere enclosing the antenna. This allowsa computationally cheap and elegant post-processing of arbitrary antenna characteristics.As an example of use the method is applied to determine high-resolution three-dimensionalradiation patterns of an antipodal Vivaldi antenna.

[学科分类] 电子、光学、磁材料