I'm not sure what the op means by QAM modultor.

An IQ modulator can in fact be used to create ANY type of modulation.

Of course you have to feed it the correct I and Q baseband signals.

Mark

On Wed, 26 Nov 2014 09:49:31 -0600, ipruzhinin wrote:

> Hi All!
> 
> It's clear how to build system when some real signal (1st real sequence)
> goes to input of Gilbert transform giving us the second (imag) sequences
> of samples.
> 
> http://www.dsprelated.com/blogimages/RickLyons/SSB-Lyons.pdf
> 
> The quiestion is - how to use Hilbert transform in QAM modulator,
> because modulator block gives us complex signal and then RRC filter
> processs the signal.

SSB modulation isn't appropriate for QAM.  If it's already in quadrature 
there's no duplication of the spectrum in baseband, which means that there 
isn't a single sideband to tease out of the baseband signal.

-- 

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Hi All!

It's clear how to build system when some real signal (1st real sequence)
goes to input of Gilbert transform giving us the second (imag) sequences of
samples.

http://www.dsprelated.com/blogimages/RickLyons/SSB-Lyons.pdf

The quiestion is - how to use Hilbert transform in QAM modulator, because
modulator block gives us complex signal and then RRC filter processs the
signal.

Thanks!!!


 

	 

_____________________________		
Posted through www.DSPRelated.com