Reconfigurable SIW-Based Leaky-Wave Antenna Composed of Longitudinal Cells

Abstract

A novel fixed frequency beam-steering leaky-wave antenna (LWA) is presented in this manuscript. Radiation occurs through thin offset longitudinal slots etched on a substrate integrated waveguide (SIW). The beam-steering is achieved by implementing GaAs varactor diodes on the backside of the antenna. Sweeping the bias voltage from 1V to 15V causes the phase constant variation, leading to the 25 • beam-steering at 28.5 GHz. The key novelties of the proposed reconfigurable antenna are the lowprofile and electronic beam-steering capability using a single varactor diode per cell located on the antenna's backside. Moreover, placing the components on the backside reduces the unwanted blockage effects on the radiation. The antenna's thickness, length, and width are 0.32 mm, 95 mm, 24 mm, respectively. The measured peak realized gain of the proposed antenna at 28.5 GHz is 9 ± 0.8 dBi. Low-profile, small gain variation, ease of fabrication, and electronic beam-steering capability make the proposed LWA suitable for the 5G beam-steering applications. A detailed sensitivity analysis along with the experimental validations were performed to prove the validity of the proposed novel design.