Understanding Fourier Series, Transform and DFT

AI Thread Summary
The discussion clarifies the distinctions among Fourier Series, Fourier Transform, and Discrete Fourier Transform (DFT). Fourier Series is specifically for periodic continuous signals, while the Fourier Transform can handle both periodic and aperiodic signals, offering a continuous spectrum. The DFT is finite due to sampling, and it provides a discrete spectrum. The mention of four versions in the Fourier family likely refers to the DFT and its faster counterpart, the Fast Fourier Transform (FFT). Understanding these differences is crucial for applying the appropriate transform to various signal types.
Jag1972
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Hello All,
I am little confused with the Fourier family of transforms. I would really appreciate it if someone could have a look at them
My understanding is as follows:

Fourier Series: Only used for Peiodic continuous signals.

Fourier Transform: Can be used for periodic or aperiodic signals, I think. This transform to me seems
to look the same as the Fourier Series its just more compact as it uses Eulers formulae and embeds the average
into the 1 summation (n=0). If signal is aperiodic then is is just assummed to be periodic.

Discrete Fourier Transform: Always finite as data is bieng sampled.

In some of the books I am reading there are 4 versions in teh Fourier family, I don't quite know why.

Thank you in advance for taking the time to help in advance.

Jag.
 
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Fourier Transform: Can be used for periodic or aperiodic signals, I think. This transform to me seems
to look the same as the Fourier Series its just more compact as it uses Eulers formulae and embeds the average
into the 1 summation (n=0). If signal is aperiodic then is is just assummed to be periodic.
The Fourier transform requires a continuous function as the input and its output is another continuous function (so the spectrum of the signal is NOT discrete). Unlike Fourier transform, Fourier serie gives a discrete spectrum, not a continuous one.
In some of the books I am reading there are 4 versions in teh Fourier family
Maybebecause there is DFT, Discrete Fourier Transform, and FFT, Fast Fourier Transform. They are similar, but the second one is faster.
 
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