Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

digital-signal-processing

Linearity and time-invariance

taught

The two properties that make a system LTI, and why LTI systems get a whole course's worth of special treatment.

Taught in

Linearity and time-invariance -- why LTI systems are special
Digital Signal Processing

Requires

discrete-time-system-properties required
sequence-shifting-and-reflection required

Required by

The convolution sum, derived from the sifting property required

Local knowledge map

Local knowledge map

Click to expand

Solid arrows are required prerequisites; dashed are recommended or helpful. Lower rows are more foundational. Click any box to jump to that concept.