https://joshuawise.com/resources/ofdm/

The Unreasonable Effectiveness of the Fourier Transform

Notes from Joshua Wise's talk at Teardown 2025.

[title]

New: You can now watch a recording of my talk on my YouTube channel!
Or you can just click "play" below, I suppose.

Here are a few resources from my talk.

  * Here is a PDF of my slides, if you wanted to refer to anything in
    specific.
  * Here is the Jupyter notebook that I used to produce all of the
    zillions of plots. I do not claim that it is good code, but it is
    code.
  * The OFDM patent is US3488445A, filed in 1966, expired in 1987.
  * Here is Eugene Wigner's original discussion, "The Unreasonable
    Effectiveness of Mathematics in the Natural Sciences". There are
    many good follow-ons to this, too.
  * Here is the paper on how to estimate both carrier offset and time
    offset at the same time. I implemented it by typing in the
    algorithm, and it worked, but if you understand it and can
    explain it to me please let me know.
  * Here is the DVB-T decoder that I wrote. I do not claim that it is
    the right way to do any of these things, but it is a way to do
    these things.
  * Finally, here is an absolutely fantastic video that breaks down
    the implementation of the Fast Fourier Transform algorithm. I
    watch it every year or two.

Thanks so much for coming! Please let me know if you have feedback on
this. I'd love to hear what you thought.

  * Joshua Wise, June 2025
  * Personal: joshua@joshuawise.com (or https://joshuawise.com/)
  * Work: joshua@accelerated.tech (or https://accelerated.tech)
  * Fediverse: @joshua@social.emarhavil.com