DAC38RF80: How to remove an image from a DAC38RF80?

Henry:

From the S/A plot it looks like you are operating with a ~6GHz sampling clock and that your desired signal (Fout) is at ~2450 MHz. The image signal is expected to be at: Fs/2 + (Fs/2 - Fout) = Fs - Fout. The delta is calculated at 2*(Fs/2-Fout) = Fs-2*Fout. There is no way to eliminate the image without external filtering.

To make the image filtering easier to deal with (and likely lower in amplitude due to sinc roll-off) you can switch to a ~9GHz clock. With this change the image delta increases from ~1.1 GHz to ~4.1GHz which will make the image filtering much easier and/or push the image to a higher frequency where it is less of a concern.

--RJH