In phase and quadrature components of a sine wave and a cosine wave

Hi,

I have a question that seems simple but is surrounding my mind. From my understanding, a signal can be represented by its in-phase and quadrature componentes (which are low pass signals). The relationship is the following

A(t)*cos(wt +phi(t) ) = si(t) * cos(wt) - sq(t) * sin(wt) , being si(t) and sq(t) the associated I and Q signals respectively.

So, imagine I have just cos(wt), does it means that si(t) is always = 1? I.e, samples IQ IQ IQ IQ IQ IQ would be

And what about sin(wt), would be sq(t) = -1 amd si(t) = 1, i.e. samples IQ IQ IQ IQ IQ IQ would be 0-1 0-1 0-1....

Regards,

--E

Later it depends then on your channel modulation technique...

You can code in three levels ( i.e -1,0,1) or 2 levels or M-levels ... but in general yeah ...your demodulated I and Q signals would follow simply as such

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Basically so ..
http://www.radartutorial.eu/10.processing/sp06.en.html