I'm looking to make a software defined radio, and I'm currently looking at what DAC to choose. I'm fairly new to this area of RF design, so I don't know what specs to look for. Most of my signals will be ~14MHz SSB transmissions (focusing on the transmitter right now). How many MSPS per second will my DAC need? Also, what bit depth should I be looking at? I've seen other designs use a low-frequency DAC, and the only reason I can see this working is if they use a frequency upconverter.
\$\begingroup\$
\$\endgroup\$
Add a comment
|
1 Answer
\$\begingroup\$
\$\endgroup\$
Ok, so after learning more about radios in general, I learned that you don't necessarily need to sample at 14MHz to digitally read a 14MHz signal. You can use a local oscillator and an RF mixer to down-convert the 14MHz down to something easier, like 1MHz. This is what you sample with the DAC. So the required DAC really depends on what intermediate frequency you choose.