Exploring the geometry of miniaturized Archimedean SPIRAL Antennas for small and portable multitask devices

Abstract

The focus of miniaturization is the production of small and portable devices that can be carried in the pocket anywhere and anytime. Small and portable devices that perform multitask such the smartphone requires a portable and efficient antenna that operates in many frequency bands. A single planar miniaturized Archimedean spiral antenna, which operates in a frequency range that is determined by its inner and outer radii of its arc, has been adjourned to be a better candidate for these multiple tasks. This study examined the geometry of a miniaturized Archimedean spiral antenna of varying turns. An inner radius of 4.90 mm and a thickness of 0.0356 mm suitable for the printed antenna were previously chosen for the study. The length of the arc and the outer radius were determined for spiral turns ranging from 0.5 to 100 with an incremental step of 0.5. Results revealed the radial distance generating the spiral, the length of its arc, the outer radius, and the surface area were 4.97 mm, 2 15.51 mm, 4.97 mm and 77.16 mm for 0.5 spiral turns, and 19.12 mm, 7,546.80 mm, 2,849.33 mm and 1,148.64 2 mm for 100 spiral turns. Based on the outer radii, the frequency range of operation will be between 16.76 MHz and 9.60 GHz. The mathematical functions formulated through curve fitting described the relationship between the outer radius and arc length with a power function and the number of turns and frequency with an exponential function, while arc length and radial distance, area and number of turns, and area and pitch angle are described by polynomial functions. It is recommended that further analysis on the geometry of the minimized Archimedean spiral antenna be conducted.