A Dual-Band Metasurface Antenna Using Characteristic Mode Analysis

A compact metasurface-based antenna is proposed for dual-band operations. The proposed metasurface is designed on a single-layered substrate including an array of modified 3 × 3 squared patches. Each of the four corner patches is split into four fractional patches while the four edge patches are evolved into Malta crosses and the center patch is scaled. A substrate integrated waveguide-based Y-junction cavity-fed dual slot drives the metasurface with multiple impedance resonances. Based on the predicted modal behaviors of metasurface using a characteristic mode analysis (CMA), as an example, an antenna operating at three resonant modes at 28, 33, and 36 GHz, respectively is designed for the dual-band operation for the coming 5G. The proposed design shows that the measured impedance bandwidths (return loss larger than 10 dB) are 23.7-29.2 GHz and 36.7-41.1 GHz with the achieved gain of 4.8-7.2 dBi and 8.9-10.9 dBi, respectively. The proposed dual-band antenna features the advantages of low profile and wideband, suitable for the coming dual-band 5G applications.