Optimization of a Compact Three-Turn Archimedean Spiral Antenna for 3 GHz High-Gain Applications

Abstract

This paper presents the design, simulation, and analysis
of a low-profile, Archimedean spiral antenna operating at a center
frequency of 3 GHz. The antenna is engineered to meet the
demands of modern wireless communication systems, specifically
targeting applications in the S-band, such as satellite
communication and radar systems. The design utilizes a two-arm
spiral geometry etched on a Rogers RT/duroid 5880 high
frequency dielectric substrate. To achieve the desired 3 GHz
operation, the physical dimensions of the spiral arms are
calculated based on the expansion rate and the start/end radii. The
antenna is designed to provide Circular Polarization (CP), which
is essential for mitigating multipath interference and signal fading.
Full-wave electromagnetic simulation results demonstrate an
excellent impedance match with a return loss of -28.65 dB and a
VSWR of 1.076 at the resonant frequency. Furthermore, the
antenna provides a stable, unidirectional radiation profile with a
peak directivity of 6.891 dBi. These results confirm the
effectiveness of the proposed Archimedean structure for compact,
high-performance S-band platforms.