Design of a Single-Layer Dual-Band and Wideband Multi-Ring Microstrip Antenna Fed by an L-probe

This paper presents design of a single-layer dual-band and wideband multi-ring microstrip antenna (MR-MSA) fed by an L-probe. The proposed antenna consists of two split ring patches arranged concentrically and a feeding L-shaped probe (L-probe) placed on a single-layer dielectric substrate. The two patches are excited by the L-probe and resonate at two different frequencies. In order to realize wideband operation, a thick dielectric substrate with a thickness of approximately 0.1 wavelengths is used. The design frequencies of the proposed antenna are around 9 GHz and 15 GHz. In this paper, the structural parameters of the proposed antenna are tuned by using ANSYS HFSS so as to obtain dual-band and wideband operation at the two design frequencies. The simulated results reveal that fractional bandwidths of less than −10 dB reflection for the two bands are approximately 10%. It is also confirmed by the simulation that stable unidirectional radiation patterns are obtained for the two bands.