Analysis of Slot Loading in Elliptical Patch- A Characteristic Mode Approach

Perturbation of the geometry through a narrow slot has been studied for an elliptical microstrip patch antenna. The loading effects have been studied from modal perspective. The slot is found to suppress the nearest orthogonal mode. As a consequence, the cross-polarized radiation is also reduced. Thus the modal analysis can provide a systematic guideline for enhancing the polarization purity of a desired mode.