The incoming 5G technology requires antennas with a greater capacity, wider wireless spectrum utilisation, high gain, and steer-ability. This is due to the cramped spectrum utilisation in the previous generation. As a matter of fact, conventional antennas are unable to serve the new frequency due to the limitations in fabrication and installation mainly for smaller sizes. The use of graphene material promises antennas with smaller sizes and thinner dimensions, yet capable of emitting higher frequencies. Hence, graphene antennas were studied at a frequency of 15 GHz in both single and array elements. The high-frequency antenna contributed to a large bandwidth and was excited by coplanar waveguide for easy fabrication on one surface via screen printing. The defected ground structure was applied in an array element to improve the radiation and increase the gain. The results showed that the printed, single element graphene antenna produced an impedance bandwidth, gain, and efficiency of 48.64%, 2.87 dBi, and 67.44%, respectively. Meanwhile, the array element produced slightly better efficiency (72.98%), approximately the same impedance bandwidth as the single element (48.98%), but higher gain (8.41 dBi). Moreover, it provided a beam width of 21.2° with scanning beam capability from 0° up to 39.05°. Thus, it was proved that graphene materials can be applied in 5G.

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The characteristics of transparent antenna for indoor television reception are investigated. It operates at Ultra High Frequency (UHF) band. The proposed antenna was made from silver coated polyester film (AgHT-4), the transparent conductive material and it is attached on a layer of glass substrate at both sides. The overall antenna length and width is at 150 mm x 50 mm. It has not fully ground plane and fed by a 50 Ω feedline. The meander line is designed at the feedline to broader the bandwidth. The simulated bandwidth obtained is 505.37 MHz to 802.45 MHz at level -6 dB. The rough impedance bandwidth is 297.08 MHz or 45.43 %. All the radiation patterns over the UHF band show bi-directional for E-plane and omni-directional at H-plane. The maximum gain obtained is 1.88 dBi.

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