QAM in SigmaStudio with ADAU1466

Hello SpenceSmit,

You may have to educate me and others on some of the details you are asking about!

QAM, Quadrature Amplitude Modulation correct? There are some different ways to do this is my very basic understanding. Are you thinking of frequency shift keying type of thing? So two frequencies, one for a zero and a different frequency for a one? This would be easy to do in SigmaStudio with two oscillators and a switch. There will probably be some small details to work out.

VIQ I could not find any info on what that is?

So educate us a bit more on your needs.

This seems like a fun challenge.

Thanks!

Dave T

Hi Dave,

Thanks for the reply! I’ll clarify.

I’m trying to implement a basic I/Q (quadrature) modulation structure in SigmaStudio rather than FSK. The approach I’m working with is to generate a baseband signal, convert it to a square wave, and then create two paths:

- An in-phase component I(t)
- A quadrature component Q(t), created by delaying the signal by 90°

Each path is then multiplied by a carrier:
- I(t) with cos(wc·t)
- Q(t) with sin(wc·t)

and the two are summed to form the output:

VIQ(t) = I(t)·cos(wc·t) + Q(t)·sin(wc·t)

So when I mentioned VIQ(t), I was just referring to the final combined I/Q modulated signal.

Hopefully that clarifies what I’m trying to do. I appreciate any insight. I’m quite new to Sigma.

Thanks

Hello SpenceSmit,

That helps a little to clear up a few things. We need more back and forth so send me a PM and also be sure to send a friend request so I can respond back.

Thanks,

Dave T

Hi Dave,

I am unable to add you for some reason - getting an error. Not able to message either. If you’d like to add and message me that would be great.