Harmonic-based nonlinearity factorization scheme to facilitate up-conversion mixer linearity

A method for designing an up-conversion mixer on a computer-aided design system, comprising:

• while executing the computer-aided design system, analyzing switching pairs of transistors for the up-conversion mixer, wherein the switching pairs use an LO signal to gate an IF input current to produce an RF output current for the up-conversion mixer, wherein analyzing each switching pair involves,
• representing a conversion of the IF input current into a common-mode source voltage for the switching pair as a nonlinear time-varying function H1, expressed as a Taylor series expansion, wherein the coefficients are expressed as a series of LO harmonics via Fourier transform,
• representing a conversion of the common-mode source voltage into the RF output current as a nonlinear time-varying function H2, expressed as a Taylor series expansion, wherein the coefficients are expressed as a series of LO harmonics via Fourier transform,
• expanding H1 into a 2D representation which relates different powers and different harmonics,
• expanding H2 into a 2D representation which relates different powers and different harmonics, and
• cascading the 2D representations of H1 and H2 to generate a set of IMD3 factors, wherein the coefficients of the 2D representation of H2 are applied to terms of H1 to generate the IMD3 factors;
• and
• designing reactive components for the common source node of the switching pair based on the determined IMD3 factors.

A non-transitory, computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for designing an up-conversion mixer on a computer-aided design system, the method comprising:

• while executing the computer-aided design system, analyzing switching pairs of transistors for the up-conversion mixer, wherein the switching pairs use an LO signal to gate an IF input current to produce an RF output current for the up-conversion mixer, wherein analyzing each switching pair involves,
• representing a conversion of the IF input current into a common-mode source voltage for the switching pair as a nonlinear time-varying function H1, expressed as a Taylor series expansion, wherein the coefficients are expressed as a series of LO harmonics via Fourier transform,
• representing a conversion of the common-mode source voltage into the RF output current as a nonlinear time-varying function H2, expressed as a Taylor series expansion, wherein the coefficients are expressed as a series of LO harmonics via Fourier transform,
• expanding H1 into a 2D representation which relates different powers and different harmonics;
• expanding H2 into a 2D representation which relates different powers and different harmonics, and
• cascading the 2D representations of H1 and H2 to generate a set of IMD3 factors, wherein the coefficients of the 2D representation of H2 are applied to terms of H1 to generate the IMD3 factors;
• and
• designing reactive components for the common source node of the switching pair based on the determined IMD3 factors.