Grid-slot Hybrid Structure Wideband Aperture Coupled Microstrip Antenna Design for C-band Applications

Abstract

An aperture coupled ψ-shaped feeding grid-slot hybrid structure microstrip antenna is proposed in this paper to enhance the gain and bandwidth. Three metallic layers are used here. The three layers consist of a radiating patch at the top, an aperture placed in ground at the middle and a feeding line at the bottom. Two dielectric layers are combined among the three metallic layers. Firstly, a line-feeding aperture coupled microstrip antenna is designed and its performances are observed. Secondly, line feeding is replaced by ψ-shaped feeding and gradually 1×1, 2×2, 3×3 and 4×4 slots are cut periodically that create 2×2, 3×3, 4×4 and 5×5 grid patches and all times the performances are observed. Among them, ψ-shaped feeding with 4×4 grid patches gets the better performances. Then, by numerically changing the dimensions of the radiating slot, coupling slot and ψ-shaped feeding size, the performances of the aperture coupled microstrip antenna are optimized. The optimized antenna shows (S₁₁ < -10dB) a bandwidth of 2760MHz (4.47-7.23GHz) and its maximum gain is 11.13dBi. C-band (4-8GHz) applications are compatible with the antenna.