Miniaturized Wideband Antenna Based on Stub-Loaded Metasurface

This paper proposes a single-layer miniaturized wide-band antenna that is based on the stub-loaded metasurface (MS) structure. The stub is loaded at the edge of a square MS cell and inserted into the gap between two adjacent cells, thereby increasing the surface capacitance and reducing the resonance frequency. Therefore, the stub-loaded MS structure can provide the resonance frequency of the conventional square MS structure while having a smaller aperture. In this way, a miniaturized wideband MS antenna based on the stub-loaded MS structure is designed. It has a bandwidth of $41 \%(4.5-6.82 \mathrm{GHz})$ and a compact size of $0.38 \lambda_{0} \times 0.38 \lambda_{0}$ (where is the wavelength at the center frequency). Compared with the conventional MS antenna, the proposed antenna smaller in size while having a large bandwidth.