Performance of Substrate Integrated Gap Waveguide Leaky-Wave Antenna on a Curved Structure

This paper investigates the radiation characteristics of substrate-integrated gap-waveguide leaky-wave antenna (SIGW-LWA) on curved structures. Placing the LWA on curvature surfaces requires conforming the antenna structure to follow the surface curvature. The radiating slot lengths are designed according to low side-lobe level Chebyshev distribution to improve the gain of the radiated beam. The gain is increased to 18.3 dBi while maximum SLL is decreased to 25 dB. An array consisting of uniformly fed two SIGW-LWA elements is investigated for high gain and low mutual-coupling. The gain is 17.5±1 dBi in the lower frequency band and is 18.5±1 dBi in the higher frequency band. The effect of the curvature radius on the propagating modes of the mushroom ridge-gap waveguide (RGW) and the LWA characteristics is studied. The peak gain is 10.5 dBi, 16.2 dBi, and 16.2 dBi for radius of curvature, R=4 mm, 8 mm, and 10 mm, respectively. The antenna is simulated and the results are analysed using CST-Microwave Studio.