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Questions and Comments for Fourier Transform of Rep and Comb Functions

A slecture by ECE student Matt Miller



Please post your reviews, comments, and questions below.



  • Review by Miguel Castellanos

I like how you state the differences between the two operators in your introduction, but then conclude by stating how the two operators are related through the Fourier transform. Your derivations are also concise. I think it would be helpful to some if you explain some of the less intuitive steps, such as when you use the Fourier series representation of an impulse train. Well done, overall.

  • Review by Hyungsuk Kim
  • I thought that this slecture is well organized in order so it was easy to follow and understand the topic. However it would be better if you put some graph to see how do they change between Rep and Comb functions.

  • Review by Soonho Kwon

Going over the equations and the mathematics, it was very clear to understand. However, to explain how the functions look like, it would be better to put some graphs on. Great job!

    • Author answer here

  • Review by Michel Olvera
    • The content of your Slecture is easy to follow. It really helped me review this topic. What I liked most was the step by step explanations and as Miguel said, few steps can be added at the end of the content to explain the Fourier Transform of the rep operator, that would be a nice improvement. Good job!

  • Review by Sahil Sanghani

Overall this is a great Slecture! I like how the derivations are concise and clear. Also, the explanations along the way draw attention to important points. I think the one spot where you could explain a little more is in the Fourier Transform of the comb. In the second line, the substitution of pT(t) with $ \sum_{n=-\infty}^{\infty}\frac{1}{T}e^{j{\frac{2 \pi}{T}}nt} $
could be better explained. Great job!


  • Review by Botao Chen

Well done. Everything is put in very good order. The demonstrations for both comb and rep are specific and easy to follow. Maybe you could try to provide some graphs to show your point. Sometimes I feel very useful to just look at the graphs and suddenly get the idea about how everything is going on.


  • Review by Randall Cochran

Great slecture. Everything was laid out in a logical and easy to follow order. One thing you could add is how you used the Fourier Series representation of the impulse train in your Fourier Transform of the comb.


  • Review by Yijun Han

The work is clear and easy to understand. The duality of the two functions rep and comb is clearly showed. The derivations for both computations are concise. Good Job.


  • Review by Yerkebulan Y.

Did not explain how to get FT of impulse train or I did not see it. Showed that comb and rep a dual functions to each other.


  • Review by Michael Hayashi

This is a high-quality slecture. Each of the main points was addressed clearly and succinctly. I liked how you developed the rep() and comb() operators in parallel to highlight the Fourier transform pair that links both of them. Though your wording was clear enough not to demand it, the only improvement I see would be including a couple archetypical graphical examples.



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