Digital-to-analog converter image suppression with hilbert transform

摘要

A method and apparatus for suppressing a first replica of an image spectra and reinforcing a second replica of the image spectra are disclosed. A Hilbert transformer is applied to a first digital signal in a first path. The Hilbert-transformed signal in the first path is converted to an analog signal in the first path. The analog signal in the first path is delayed by an additional 90 degrees to produce a first phase-shifted analog signal. A phase delay is applied to the first digital signal in the second path and the phase-delayed signal in the second path is converted to analog to produce a second phase-shifted analog signal. A combiner combines the first and second phase-delayed analog signals to produce an analog output signal with at least one replica of the image spectra that is substantially suppressed.