Performance Analysis Of Hybrid Metal-Graphene Frequency Reconfigurable Antennas In The Microwave Regime

This paper analyses the potential application of graphene in microwave frequency reconfigurable antennas. Two multi-band designs, one for wireless local area networks (WIFI), covering the frequency bands of 2.4 GHz, 3.6 GHz and 5 GHz; and another for the cellular long term evolution (LTE) system, operating the frequency bands of 1.8 GHz, 2.5 GHz, 2.6 GHz and 3.6 GHz; are evaluated to demonstrate the working principle and the performance trade-offs. The designs are made mostly of copper with some parts made of graphene to enable reconfigurable behaviour. The graphene material’s surface impedance is tuned by applying a DC bias voltage which allows to obtain one of two extreme values that emulate the ON and OFF states of common switches such as Micro Electromechanical Switches (MEMS), Field effect transistor (FET) and Ptype
Insulator N-type (PIN) diode, or continuous values to mimic reconfigurable antennas loaded by varactors. This material switching modifies the electrical length of the current propagating through the antenna and consequently switches the resonant frequencies. Additionally, results show that hybrid metal-graphene frequency reconfigurable antennas can, at the same time, provide tunable bandwidth and antenna matching.