Millimeter-Wave Projectile Conformal End-Fire Antenna for Fuze Radar Application

This paper presents the development and implementation of a novel millimeter-wave conformal end-fire antenna exploiting the principle of surface wave modulation. The design capitalizes on the inherent property that electromagnetic waves propagate at varying velocities in distinct media, enabling the modulation of surface waves to manifest an end-fire radiation pattern by employing a dielectric substrate with specific permittivity and thickness atop a metallic structure. The proposed antenna demonstrates an average gain performance of 12.9 dBi within the operational frequency band spanning from 32.1 GHz to 36.7 GHz. Moreover, it exhibits a front-to-back ratio of 21.3 dB and maintains cross-polarization levels below -25 dB. Notably, this innovative design approach enables the realization of a conformal end-fire antenna without introducing beam upward deflection, a significant advantage in many applications. Meanwhile, the radiation performance remains steadfast even when the size of ground plane varies. Experimental results robustly validate the applicability of this antenna for use in millimeter-wave end-fire systems that necessitate conformation to curved surfaces.