Estimating the near field coupling from SMPS circuits to a nearby antenna using dipole moments

Abstract

In this paper, the near field coupling from SMPS circuits to a nearby antenna is studied using dipole moments [1]. The dipole moments are extracted from scanned H fields on a plane above SMPS circuits, and then imported into an HFSS model to do full wave simulation. The simulated coupling matches well with direct measurement. Methods to resolve magnitude and phase of near fields of SMPS noise source are introduced. Error analysis is included in the end as well.