A New Method Exploiting Partial Image Expansion to Include Substrate and Ground in Dipole-Based Near-Field Models

This work introduces a novel method to include the passive structure of a printed circuit board into an infinitesimal dipole model that is reconstructed from near-field measurement data. Specifically, the proposed approach enables the construction of equivalent models that include dipole sources, substrate, and perfect electric conductor plane. The electromagnetic near-fields of the infinitesimal dipoles in this configuration are estimated through an adaptation of the partial image expansion technique. The proposed method has the capability to provide accurate results for a wide variety of configurations. Furthermore, it can be easily incorporated into existing dipole array optimization workflows with minimal added computational complexity.