Radio frequency circuit with back gate-assisted mixing of radio frequency and local oscillator signals

Abstract

A combined low noise amplifier (LNA), mixer, and voltage-controlled oscillator (VCO) circuit (i.e., an LMV cell) includes four dual-gate transistors. These four transistors include series-connected first and second transistors between a ground rail and a first local oscillator signal node and series-connected third and fourth transistors between the ground rail and a second local oscillator signal node. The first and third transistors are LNA components. The second and fourth transistors are cross-coupled VCO components. Front and back gates of the transistors are biased with different combinations of an RF input signal and complementary local oscillator signals generated on the first and second local oscillator nodes. This front and back gate biasing effectively mixes the RF input signal with each of the complementary local oscillator signals to generate complementary intermediate frequency output signals at output nodes between the first and second transistors and between the third and fourth transistor, respectively.