Tunable Array Antenna with CRLH Feeding Network Based on Graphene

This paper introduces a novel design of compact tunable monopole antenna array, employing composite right/left handed (CRLH) feeding network. The feeding network configuration is coplanar waveguide (CPW). A graphene sheet is placed beneath the CRLH cell to achieve the tunability behavior in the antenna design. The antenna array configuration achieves the tunability function with an accepted gain. The surface conductivity of the graphene sheet is tuned by changing the applied DC bias voltage. The DC voltage changes the chemical potential of the graphene sheet. The antenna array is tuned from 2.5-2.46, 2.43, and 2.42 GHz when the chemical potential of graphene is changed from 0.0, 0.15, and 0.2 eV, respectively. The array antenna has a reasonable gain of 5.34 dB without placing the graphene sheet. By placing the graphene and changing the chemical potential, the array gain values become 4.42, 3.82, and 3.74 dB at the specified chemical potential. The radiation properties of the array are studied at the desired resonant frequency. The proposed design can be fabricated by using the transparent transfer process. All the presented designs are verified using the electromagnetic solver CST Studio.