Dissipation Factors of Spherical Current Modes on Multiple Spherical Layers

TL;DR

This paper presents a rigorous method to evaluate the dissipation factors of spherical current modes on multi-layered shells, providing closed-form expressions and insights into radiation efficiency improvements.

Contribution

It introduces a new approach for calculating dissipation factors on multi-layered spherical shells and compares it with existing models, analyzing discrepancies and implications.

Findings

Closed-form expressions for dissipation factors on spherical shells.

Comparison reveals discrepancies with existing models.

Internal volume use can enhance radiation efficiency.

Abstract

Radiation efficiencies of modal current densities distributed on a spherical shell are evaluated in terms of dissipation factor. The presented approach is rigorous, yet simple and straightforward, leading to closed-form expressions. The same approach is utilized for a two-layered shell and the results are compared with other models existing in the literature. Discrepancies in this comparison are reported and reasons are analyzed. Finally, it is demonstrated that radiation efficiency potentially benefits from the use of internal volume which contrasts with the case of the radiation Q-factor.