The radiation properties of a copper-patch antenna designed for resonating at the frequency of 0.7 THz, which is used in aerospace applications, is presented. These properties are then compared to those of a graphene-patch antenna presenting the same dimensions. We show how the use of graphene, as a tunable material, allows to dynamically modify the frequency of operation of the antenna as well as its radiation pattern. Our results show that the return loss peak reaches -29 dB, at the operating frequency, which is almost twice the value obtained with the copper patch. This increase in the return loss peak is also accompanied by an improvement in the gain of the antenna from 5.73 dB in the case of the copper patch to 7.16 dB in the case of graphene. We focus our interest on how the reconfigurable radiation properties of the graphene-patch antenna are directly related to the graphene surface conductivity.
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