Trade-off Between Antenna Efficiency and Q-Factor

TL;DR

This paper formulates the trade-off between antenna efficiency and Q-factor as a multi-objective optimization problem, revealing the costs and effects of design choices on small antennas' performance.

Contribution

It introduces a novel multi-objective optimization framework to analyze the trade-offs between efficiency and Q-factor in small antennas, including various design constraints.

Findings

Pareto-optimal sets illustrate efficiency vs. Q-factor trade-offs

Self-resonant current requirement impacts efficiency significantly

Lossy parasitic loading affects antenna performance

Abstract

The trade-off between radiation efficiency and antenna bandwidth, expressed in terms of Q-factor, for small antennas is formulated as a multi-objective optimization problem in current distributions of predefined support. Variants on the problem are constructed to demonstrate the consequences of requiring a self-resonant current as opposed to one tuned by an external reactance. The resulting Pareto-optimal sets reveal the relative cost of valuing low radiation Q-factor over high efficiency, the cost in efficiency to require a self-resonant current, the effects of lossy parasitic loading, and other insights.