Patent ID: 7890076

Claim:
A receiver circuit comprising: a low-noise amplifier circuit providing one or more output signals; a mixer circuit having two or more signal inputs, wherein the mixer circuit includes one or more mixer cores and one or more single-ended termination circuits; wherein the two or more signal inputs of the mixer circuit are coupled to inputs of the one or more mixer cores, with each of the two or more signal inputs being associated with the one or more single-ended termination circuits; and a capacitive coupling circuit comprising a coupling capacitor for each signal input of the mixer circuit, each said coupling capacitor coupling one of said one or more output signals from the low-noise amplifier to a respective one of said two or more signal inputs; wherein the coupling capacitors are all matched in capacitance and the value of that capacitance is sized to reduce a sensitivity of the receiver circuit to imbalances in mixer transconductance between the signal inputs of the mixer circuit, and, in particular, wherein each coupling capacitor is sized such that ωC≦g m , where ω is a frequency of interest, C is the capacitance value of the coupling capacitor, and g m is a transconductance value of the one or more mixer cores.