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Measurements >> Phase Noise and Jitter Measurements >> Specrum analyzer measurement principles' question
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Message started by neoflash on Oct 30^th, 2005, 1:49am

Title: Specrum analyzer measurement principles' question
Post by neoflash on Oct 30^th, 2005, 1:49am

Hi, Folks:

I am curious about how machine spectrum analyzer calculate the PSD of input signal.

In Parcevall law:

Integrate (f(t)^2) = Integrate (F(s)^2) ;

In left side of equation, original law said that the integration start from -T to +T. (T is measurement interval)

However, in real world, f(t) is always zero when time is negative.

So, the final PSD is get from divide both sides by T, or 2T? I think it should be T, is that right?