Highly Compact and Cost-Efficient Metal-Coated UWB 3D Vivaldi Radial Array for RADAR Applications

This study introduces a compact and cost-effective metal-coated ultra-wideband (UWB) 3D Vivaldi antenna (VA) and its associated radial array designed for Radio detection and ranging (RADAR) applications. The proposed 3D radial Vivaldi antenna array (RVAA) comprises eight outer radial elements positioned at angular intervals of 45 0, along with four inner radial elements strategically located to maintain 90° angular spacing between them to enhance gain in end-fire direction and to mitigate side lobe issues. Thus, the array encompasses a total of twelve 3D Vivaldi antenna elements arranged radially. Each antenna element is bottom-fed through coaxial SMA ports individually. The array features an aperture diameter of 84 mm and a base thickness of 12 mm. Operating within the frequency range of 3.3 GHz to 11.9 GHz, the proposed antenna array achieves a peak gain of 20 dBi at a center frequency of 7.6 G Hz. Fabrication of the proposed antenna is envisioned to utilize Acrylonitrile butadiene styrene (ABS) plastic-based 3D printing combined with electroplating techniques, aimed at reducing fabrication costs without compromising antenna performance. Consequently, the proposed radial 3D Vivaldi antenna array offers a promising alternative to prohibitively expensive all-metal antennas and holds significant potential for ultra-wideband RADAR applications.