Harmonic cancellation for frequency conversion harmonic cancellation

摘要

A radio frequency (RF) receiver, such as a television tuner, includes a harmonic cancellation circuit. The harmonic cancellation circuit includes a primary signal path to generate a first intermediate frequency (IF) signal by mixing an RF signal with a reference signal and a harmonic feedforward signal path to generate a second IF signal representing signal content of the RF signal near an nth-order harmonic of a frequency f_LO of the first reference signal, n comprising a positive integer. The harmonic cancellation circuit further includes a summation stage to generate a third IF signal based on a difference between the first IF signal and the second IF signal.