Frequency-Reconfigurable Microstrip Patch Antenna Based on Graphene Film

Abstract

Fifth-generation mobile communication systems must connect to multiple wireless networks. In order to enable a single device to match the frequency bands of multiple wireless networks, it is usually necessary to use multiple single-band or multi-band antennas, which occupy a large amount of space inside a given device. Using frequency-reconfigurable antennas to replace multiple single-function antennas is an effective way to solve this problem. In this paper, we propose a frequency-reconfigurable microstrip patch antenna based on graphene film, which fills the slot of the radiating patch with graphene film. It was found that the surface current of the antenna can be changed by changing the conductivity of graphene through bias voltage, which allows the operating mode of the antenna to switch between a nearly slotted antenna and a nearly unslotted antenna to achieve frequency reconfigurability. By changing the bias voltage from 0 V to 9 V, the resonant frequency of the antenna can be switched from 29.6 GHz to 40 GHz, and the center frequency can by altered by 10.4 GHz, corresponding to the reflection coefficients of −26 dB and −20.8 dB, respectively. The antenna achieves good matching in both operating modes.