Previous Entry Share Next Entry

Think DSP

A few months ago, Professor Allen Downey of Olin College wrote to me about a DSP textbook he's working on at He sent me links to his chapter about the sampling theorem, plus a blog post with an iPython notebook for playing with sampling a bit.

[I've been meaning to write back ever since, but I royally suck at email. So let me blog about it first, then perhaps extend the minimal courtesy of actually writing back.]

As he puts it, his approach is computational. Where many books on sampling and DSP in general throw a lot of dry equations at you without explaining much practical context (and I take the opposite approach, providing intuition and context, leaving the math out almost completely), he explores the practical arithmetic that gets us from point A to point B. "What happens if I do this..."

It's a slightly sneaky approach that builds up toward sampling through AM modulation (yes, as in AM radio), but this works toward a great illustration of how the Nyquist rate, the sampling theorem, and time-frequency duality aren't just sideshow theory, or a bag of cute tricks. They're practical truth that underlies nearly everything we do with signals and audio, even when we're neither sampling, nor working digitally.

Tags: , ,

Recent Posts from This Journal

  • George makes it his own

    Last summer I bought a house in New Hampshire for living as well as greatly expanded workshop space. The kids are up here about half the time, and…

  • Shhh sh sh shhhh..... I'm making..... TOAST!

    It's an old pic at this point (taken while TD, aka, @enginetankard was still here in January) but I can't mention 'laser cutter progress'…

  • Oh right, about those LEDs

    spoiler: Nichia Rocks. But first a flashback. Remember those crazy Chinese LEDs I was looking for? They had kind of iffy construction, but up…


Log in