Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

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

Status
Not open for further replies.
0

0xEthan

Newbie level 6
Joined
Apr 11, 2012
Messages
11
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,369
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

- - - Updated - - -

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

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top