Low-profile radome-optimized high-gain series-fed array antenna for W-band radar applications

Abstract

In this article, a new series-fed array antenna optimized with a low-profile radome is proposed for W-band compact radar applications. The proposed high-gain antenna array features a planar structure incorporating parasitic patches and shorting pins through a series-fed network. Due to the high-gain characteristic of the proposed antenna, the height of the radome, typically used as an antenna cover while further enhancing the directivity of radar applications, can be significantly reduced. To demonstrate the efficacy of the proposed antenna array in enhancing directivity and thereby reducing the radome profile, 4 × 4 arrays with conventional and proposed series-fed structures were both designed and compared. Both series-fed array antennas were fabricated on the same-sized ground plane of 12.9 λ₀ × 10.5 λ₀ at 80 GHz, including extra space for radome assembly. The simulated gains for the conventional and proposed series-fed array antennas were 15.7 dBi and 18.3 dBi at 80 GHz, respectively. Radomes for both array antennas, designed to achieve a narrow beamwidth of less than 15°, were fabricated using a 3D printer. The simulated and measured normalized radiation patterns showed excellent agreement, with measured half-power beamwidths of less than 14°. With similar antenna radiation characteristics, the proposed series-fed array antenna demonstrated a 35.9 % reduction in the required radome height compared to the conventional series-fed configuration.