How Do I Apply Parseval's Theorem to a Modulated Signal in the Frequency Domain?

AI Thread Summary
The discussion revolves around applying Parseval's theorem to a modulated signal in the frequency domain, specifically for a squaring function. The user presents the modulated signal W(w) and seeks clarification on how to compute Z(ω) using the theorem. They express confusion about integrating the squared magnitude of W(w) and whether to consider the integral over specific intervals. The response emphasizes that while Parseval's relation reflects energy conservation, it may not directly apply to calculating Z(ω) in this context. Overall, the conversation highlights the complexities of using Parseval's theorem for squaring functions in frequency analysis.
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Alright. So... Conceptually I completely understand what I'm doing. I'm just a bit confused about how, mechanically, to solve this.

I basically have the following:
W(w)=(1/2)[p2(w+6)+p2(w-6)]

Where p2(w) is a pulse of width 2. Of course, w is omega, and the +/-6 is the shift. This is a modulated signal and it's in the frequency domain. Now this is my problem...

w(t) is put into a squaring function, which produces z(t).

In this problem, the frequency domain is infinitely easier to work with than the time domain. So I know I can use Parseval's theorem, the special case for squaring a function. My problem is that I am then presented with the followingI'm using:

\int_{-\infty}^{\infty}x^2(t)dt=\frac{1}{2\pi}\int_{-\infty}^{\infty}|X(\omega)|^2d\omega

Can I say that

<br /> Z(\omega)=\frac{1}{2\pi}\int_{-\infty}^{\infty} | \frac{1}{2} <br /> [ p_{2}(\omega + 4)+p_{2}(\omega - 4)] |^2 d \omega<br />?How do I deal with this integral? Do I just simply take the integral of the height of W(w) from -7 to -5 and then from 5 to 7 and just add them?

Am I supposed to end up with T/2, where T=the width of my pulse??Any suggestions would be greatly appreciated. Thanks
 
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The Parseval's relation gives you the concept of law of conservation of energy. Both RHS and LHS are just real numbers. You can use frequency domain stuff to calculate Z(\omega) but not by using Paarseval's relation.
 
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