Frequency-reconfigurable slot antenna with wide-tuning range using metasurface

Abstract

A frequency-reconfigurable slot antenna designed using metasurface (MS) is proposed in this paper. The frequency-reconfigurable metasurfaced (FRMS) antenna is composed of a simple slot antenna and a MS, both having a circular shape with the same diameter of 50 mm (equivalent to 0.5λ0 where λ0 is the operating wavelength in free space) and implemented using planar technology. The MS consists of rectangular-loop unit cells, with a large length-to-width ratio, placed periodically in the vertical and horizontal directions. The MS is placed directly on top of the slot antenna, making the FRMS antenna very compact and low profile with a thickness of only 3.048 mm (0.03 λ0). The operating frequency of the antenna can be tuned by physically rotating the MS around the center with respect to the patch antenna. The antenna is studied using computer simulation. For verification of simulation results, the FRMS antenna is fabricated and measured. Simulated and measured results agree very well. With the use of a large length-to-width ratio in the rectangular-loop units cells and slot antenna which has a wide bandwidth, results show that the proposed RFMS antenna has a wide tuning range of 28% (from 2.64 to 3.5 GHz). © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1475–1481, 2015