A Nearly All-Digital Frequency Mixer Based on Nonlinear Digital-to-Analog Conversion and Intermodulation Cancellation

We propose a nearly all-digital frequency mixer producing either the sum or difference of two frequencies provided as digital clocks. No filtering of the clock inputs is needed to suppress intermodulation products at the output. The mixer achieves high spurious-free dynamic range through optimization of an output nonlinear DAC and a multiphase intermodulation cancellation technique. A programmable logic implementation demonstrates feasibility and performance of the architecture.