1. An up-conversion mixer, comprising: a mixer cell having at least one output node configured to generate an output; a first cascaded transconductance input stage coupled to the mixer cell, the first cascaded transconductance input stage configured to receive an input signal and to reduce a third order harmonic of the output; and a second cascaded transconductance input stage coupled to the mixer cell, the second cascaded transconductance input stage configured to receive the input signal and to reduce the third order harmonic of the output, wherein the third order harmonic is reduced to have a first magnitude at a first input signal power level smaller than a second magnitude at a second input signal power level, the second input signal power level being lower than the first input signal power level.