Design of a cavity-backed spiral antenna using frequency-dependent impedance of a stepped-width arm for low frequency gain enhancement. Issue 2 (17th February 2020)

• Record Type: Journal Article
• Authors: Hur, Jun; Choo, Hosung
• Is Part Of: Electromagnetics. Volume 40:Issue 2(2020)
• Page Start: 93
• Page End: 103
• Publication Date: 2020-02-17
• Subjects: Spiral antenna -- Stepped-with arm -- Single arm -- Cavity-backed structure; Electromagnetism -- Periodicals; 537
• DOI: 10.1080/02726343.2019.1710682
• Languages: English
• ISSNs: 0272-6343

Abstract

ABSTRACT: This paper proposes a stepped-width spiral antenna for gain enhancement at a low operating frequency. The frequency-dependent characteristic of the stepped-width transmission line is applied to the spiral arm to enhance the gain at the low end of the operating frequency, and a cavity-backed ground is added to the bottom side of the antenna to further improve the gain at the bore-sight direction. To verify the gain enhancement at the low operating frequency and impedance matching characteristic, we observe the antenna performances such as bore-sight gains and reflection coefficients according to the shape of the spiral arm. The results confirm that the proposed stepped-width structure can enhance the gain at the low operating frequency by improving the impedance matching characteristic.