Analysis of graphene based optically transparent patch antenna for terahertz communications

• Application of graphene as a transparent conducting material for the patch antenna with and without MWCNT short is analyzed in the 5.66–6.43 THz band.
• The MWCNT loaded graphene based antenna yields a return loss improvement of 9.38dB as compared to that without the MWCNT loaded antenna.
• Both the transparent antennas achieved broad bandwidth (12.83%), high directivity (7.56dB), and high gain (≥2dB).

With and without multi walled carbon nanotube (MWCNT) loaded graphene based optically transparent patch antennas are designed to resonate at 6 THz. Their radiation characteristics are analyzed in 5.66–6.43 THz band. The optically transparent graphene is deployed as the patch and ground plane of the antennas, which are separated by a 2.5 μm thick flexible polyimide substrate. By shorting the microstrip line and ground plane of the antenna with a MWCNT via, the return loss of the antenna is improved. The peak gain of 3.3dB at 6.2 THz and a gain greater than 3dB in 5.66–6.43 THz band is obtained for antenna loaded without MWCNT. Both the antennas achieved a −10dB impedance bandwidth of 12.83%. Gain, directivity and radiation efficiency of the proposed antennas are compared with conventional transparent patch antennas and graphene based non-transparent antennas. The antenna structures are simulated by using finite element method based electromagnetic simulator-Ansys HFSS.

By shorting the microstrip line and ground plane of the antenna with a MWCNT, the return loss of the antenna is improved. It is observed that the return loss of −48.75dB is obtained for a MWCNT loaded antenna as compared to −39.37dB obtained for that without a MWCNT loaded antenna. Return loss improvement of 9.38dB is achieved for antenna loaded with MWCNT. Thus by optimizing the position of the MWCNT short return loss of the antenna is significantly improved for the same impedance bandwidth. Both the graphene based transparent antennas achieved the −10dB impedance bandwidth of 12.83%. The graphene based transparent antennas have broad bandwidth (12.83%), high directivity (7.56dB) and high gain (≥2dB).Figure optionsDownload as PowerPoint slide