Dual-band metasurface-based CP low-profile patch antenna with parasitic elements

Abstract

A single-feed dual-band circularly polarised (CP) patch antenna is proposed. The antenna consists of a corner-truncated square patch antenna and a superstrate composed of a lattice of 2 × 2 metallic patches surrounded by parasitic elements. The driven patch generates one resonant mode. The metasurface with parasitic elements excites two additional resonant modes (TM10 and TM20). The combined resonances result in minimum axial ratio points, and a good dual-band CP operation is achieved. Simulations show that the antenna has a CP operating bandwidth of 40 MHz centred at 3.72 GHz (1.07%), and a CP operating bandwidth from 5.37 to 6.05 GHz (11.9%). The simulated gain is ∼7.05-7.1 dBic for the low-frequency band and 4.17-6.07 dBic for the high-frequency band, respectively. Measurements and simulations are in good agreement.