Skip to content
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

The discrete-time Fourier transform (DTFT), defined

taught

The forward and inverse DTFT sum/integral, and what it means for a discrete sum to produce a continuous-frequency function.

Taught in

Requires

Required by

Local knowledge map

Local knowledge map

Sinusoidal steady-state response The four Fourier representations, unified The z-transform: definition, region of convergence, and… DTFT properties -- time reversal and frequency shift Magnitude and phase spectra Periodicity of the DTFT Reading a system's frequency response off its difference… Why a transform beyond the DTFT is needed The discrete-time Fourier transform (DTFT), defined A gallery of standard Fourier transform pairs Differentiation in time is multiplication in frequency Linear constant-coefficient difference equations The Fourier convolution theorem The Fourier transform in several dimensions, and separability Discrete-time sinusoid periodicity's frequency-domain… Linearity, shifting, scaling, and duality of the Fourier… Deterministic vs. random, periodic vs. aperiodic signals The Fourier transform, and its inverse

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.