Sawtooth wave spectrum

Question

The Fourier transform of a periodic signal is a pulse train, but for a sawtooth wave, what is the fundamental frequency of the spectrum?

Thanks

You heard wrong. A pulse train is it's own Fourier transform. Also, you'll have to reword what you mean by the fundamental frequency of the spectrum. Since the spectrum of a sampled signal repeats every $2\pi$ radians/sample, one might say that is the fundamental frequency of them all. — AnonSubmitter85, Jun 23 '13 at 09:11

score 1 · Answer 1 · answered Jun 03 '13 at 21:33

1

The fundamental frequency is the inverse of the period (if you measure phase in cycles) or $2 \pi$ divided by the period (if you measure in radians). The Fourier expansion is shown here as $\dfrac 2\pi\displaystyle \sum_{k=1}^{\infty}(-1)^{k+1}\frac {\sin(2k\pi f t)}k$

answered Jun 03 '13 at 21:33

Ross Millikan

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Thanks, but I think you are explaining the fourier series not the fourier transform. – JMFS Jun 03 '13 at 22:12
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For a periodic function, they are the same. There is only energy at harmonics of the period. – Ross Millikan Jun 03 '13 at 22:47
Thanks, it's true. In a fourier series, the non-integer samples are always zero. – JMFS Aug 10 '20 at 01:12

Sawtooth wave spectrum

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