An ESPAR Antenna with Omnidirectional and Steerable Patterns for V2XApplications

An electronically steerable parasitic array radiator (ESPAR) antenna with omnidirectional and 360° steerable patterns is proposed for vehicle-to-everything (V2X) applications. The antenna has a compact size and consists of a driven monopole in the middle and eight parasitic monopoles placed on a circle with equal distances between them. Each parasitic monopole is connected to the ground plane through a PIN diode. The omnidirectional pattern is achieved by turning off all PIN diodes. The directional radiation patterns with steerable capability can be achieved by turning on four adjacent PIN diodes. A sleeve is designed around the driven monopole to reduce the size of the antenna. Computer simulation has been used to study, design, and optimize the antenna. Results show that the proposed ESPAR antenna can be operated in both omnidirectional and directional states in 2.4-2.48 GHz and achieves beam steering in the azimuth plane with maximum gain of 6.52 dBi and the front-to-back (FB) ratio of 17 dB.