A Subharmonic Graphene FET Mixer

Abstract

We demonstrate a subharmonic resistive graphene FET mixer utilizing the symmetrical channel-resistance versus gate-voltage characteristic. A down-conversion loss of 24 dB is obtained with f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RF</sub> = 2 GHz, f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LO</sub> = 1.01 GHz, and f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">IF</sub> = 20 MHz in a 50- Ω-impedance system. Unlike conventional subharmonic resistive FET mixers, this type of mixer operates with only one transistor and does not need any balun at the local oscillator (LO) port, which makes it more compact.