Design of spiral antenna using a Vivaldi-shaped balun

ABSTRACT

This paper proposes a design of a spiral antenna using a Vivaldi-shaped balun for broadband matching characteristic with high tolerance to fabrication error and low geometrical complexity. The proposed antenna consists of spiral arms, a Vivaldi-shaped balun, and a ground with a cavity-backed structure. The Vivaldi-shaped balun is connected to the spiral two arms to obtain broad matching characteristics, and the cavity-backed structure is employed to achieve a high directivity. To verify proposed antenna performance, such as reflection coefficients, bore-sight gains, and radiation patterns, the antenna is measured in a full anechoic chamber. The results confirm that the proposed antenna is suitable for broadband spiral antennas with high tolerance to fabrication error and low design complexity.

KEYWORDS:

• Spiral antennas
• Vivaldi-shaped balun
• Hybrid antenna

Additional information

Funding

This work was supported by the research fund of the Signal Intelligence Research Center supervised by the Defense Acquisition Program Administration and Agency for Defense Development of Korea.