Fig. 1: Antenna systems for sub-THz transmission.
From: Sub-THz wireless transmission based on graphene-integrated optoelectronic mixer
In these scenarios a graphene optoelectronic mixer could be used inside a transmitter to perform frequency upconversion. In red, point-to point links, allowing directional communications between two fixed network nodes. In green, point-to-multipoint links using phased-array antenna allowing to reach multi-users through beamforming, including objects in movement. In blue, automotive RADAR sensing for, e.g., autonomous driving. Each node of the network contains a frequency converter that allows the upconversion of a baseband information in the sub-THz frequency range. A graphene optoelectronic mixer (G-OEM), shown on the right, is a miniaturized object that can be potentially used in all these scenarios to perform frequency upconversion of baseband signals in the sub-THz range, in a very effective way. The device uses an optical local oscillator (LO) constituted by two optical wavelengths (λ1,λ2) instead of an electrical LO, thus performing excellent stability and easy tunablity of the sub-THz carrier frequency (CF), allowing, e.g., the realization of compact phased-array antenna systems based on optoelectronics.
