Digital upconverter for radio frequency sampling transmitter

A system, comprising:

• conjugate-mixer-combiner including:
• a pre-combiner configured to generate first and second combinations of:
• a first in-phase (I) value to be transmitted at a first frequency of a first frequency band;
• a first quadrature (Q) value to be transmitted at the first frequency of a first frequency band;
• a second I value for to be transmitted at a second frequency of a second frequency band;
• and
• a second Q value to be transmitted at the second frequency of a second frequency band;
• a first multiplier coupled to the pre-combiner and configured to shift the first combination based on an average difference between the first frequency and the second frequency;
• and
• a second multiplier coupled to the pre-combiner and configured to shift the second combination based on an average difference between the first frequency and the second frequency.