On using graphene-based conductors as transmission lines for feed networks in printed antenna arrays

The use of graphene-based conductors (GBC) as a transmission line (TL) is presented as a conventional TL possessing right-handed (RH) nature and its coupling characteristics are investigated. In order to verify and demonstrate the wave propagation of a GBC TL, a 120 mm long 50 Ω TL was fabricated and tested. Performance of the single GBC TL was then compared to the conventional microstrip TL, analyzing the matching and wave propagation results. To investigate the unwanted coupling that may occur in a feed network, a similar GBC and a conventional microstrip TL, as well as two parallel GBC TLs on the same substrates were separately manufactured and tested to complete the study. It is shown that GBC TLs support the wave propagation in a fashion similar to the microstrip TL with an attenuation of less then 3.0 dB up to 7 GHz. Also the measurements of the near-end coupling showed that the two parallel GBC TLs have fairly good isolation in the frequency band of 4.5 KHz to 8.5 GHz, whereas the far-end coupling exhibits similar properties to that of the parallel microstrip TLs with same distance between them. The results demonstrated that GBC TLs could hence be a potential candidate for the feed network for planar antenna arrays.