A Visual Introduction to DSP for SDR

This is an animated slide deck providing a tour of digital signal processing topics relevant to implementation of software-defined radios, focusing on building visual/geometric intuition for signals.

Topics covered:

• Complex (IQ) and analytic signals.
• Filtering (FIR and IIR).
• Frequency shifting.
• Sampling rates and the Nyquist limit.
• The discrete Fourier transform (DFT) and fast Fourier transform (FFT).
• Digital modulation (OOK, PSK, QPSK, QAM).

View the interactive slides. Requires WebGL.

(Keyboard controls: left/right arrows to change slides. Space to pause/resume live signal. T to pause signal until a loud moment and resume.)

Or, watch a recording of me giving the presentation at Balint Seeber’s Cyberspectrum, November 2014. Note that this version does not include the material on digital modulations.

Source code, and issue tracker with future plans.

Note: The presentation will request access to your microphone. This access is used only to display live audio. The audio will not leave your computer, and the page is on a subdomain so that your authorization doesn’t carry over to anything else I might make.