Re: what is the frequncy spectrum of a clock signal?

a. There is no dc offset to any signal
b. Yes, I plotted the FFT of the signal in MATLAB but I didn't get
what I expected.
On Apr 23, 8:36 pm, dbell <bellda2...@xxxxxxx> wrote:
On Apr 23, 11:29 am, apurva <agarwal.apu...@xxxxxxxxx> wrote:



hi all,

I am having difficulty coming to the mathematical solution to the FT
of a periodic clock signal. Simple logic tells me that the signal
power should be concentrated at the fundamental frequency (ie the
clock freq) present in the signal. But when I solve it using the DTFT,
I get the representation as the Sampled sinc function which implies
that all my signal informatio(and power) is concentrated in the
baseband near the zero frequency , which is contradictory to the prior
statement.

Similar situation arises when I try to get the spectrum of a periodic
triangular wave(which can be thought of as an rough approximation of a
sine-wave). Hence the signal power should be centred at the
fundamental frequency and not the base freq. But I cannot conclude
this result mathematically. Is there a flaw in the basic mathematics
involving this? Or am I overlooking something really really
fundamental?

Can someone help me get a clearer picture of things?

Thx and regards
apurva

Is there a non-zero DC offset to your clock signal?

Have you tried putting of what you think the clock signal should look
like into the FFT and see if you get the results you expect?

Dirk


.

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