The performance improvement of thz antenna via modeling and characterization of doped graphene

The improvement of Terahertz (THz) antenna requires efficient (nano)materials to operate within the millimeter wave and THz spectrum. In this paper, doped graphene is used to improve the performance of two types of patch antennas, a rectangular and an elliptical antenna. The surface conductivity of conventional (non-doped) graphene is first modeled prior to the design and simulation of the two graphene based antennas in an electromagnetic solver. Next, different graphene models and their corresponding surface conductivities are computed based on different bias voltages or chemical doping. These configurations are then benchmarked against a similar antenna based on conventional metallic (copper) conductor to quantify their levels of performance improvement. The graphene based antennas showed significant improvements for most parameters of antenna than that of the conventional antenna. Besides that, the higher chemical potentials resulting from higher biasing voltages also resulted in this trend. Finally, the elliptical patch graphene antenna indicated better reflection performance, radiation efficiency and gain than a rectangular patch operating at the same resonant frequenc

Modeling and performance evaluation of antennas coated using monolayer graphene in the millimeter and sub-millimeter wave bands

Abstract In the applications of millimeter and sub-millimeter wave, the conductivity of metal parts in electronic devices can easily degrade when conventional metals like copper are employed. Furthermore, oxidation may arise when such devices are utilized in severe environmental conditions. To avoid this, conventional conductors such as copper can be coated with other non-active materials to inhibit this problem. Monolayer graphene is used in this study as a coating layers for copper in millimeter-wave antennas. Two types of graphene coatings are investigated: non-doped and doped monolayer graphene. These coatings can either be used as the patch, ground or both conducting layers of a microstrip patch antenna. Results showed that coating using doped graphene improves the performance of antenna in terms of gain, radiated power and radiation efficiency by 11.81%, 8.48%, and 11.48%, respectively, compared to antennas made using copper and coated using gold and non-doped graphene at millimeter-wave frequencies. Meanwhile, at sub-millimeter wave frequencies, the metal (copper and gold)-based antenna showed worse performance compared to millimeter waves. Furthermore, coating of the conducting elements for the sub-millimeter wave antenna using doped and non-doped graphene improved gain, radiated power and radiation efficiency by 33.94%, 32.73%, and 32.01%, respectively, for the coating with doped graphene, and about 14.87%, 16.56%, and 15.72% for the coating with non-doped graphene. This indicates the suitability of graphene-based antennas in both frequency bands and the expected levels of improvements for different parameters when these antenna elements are coated with doped and non-doped graphene