Drag blocks. Watch signals. All in the browser.

01 · WHAT IT DOES

Build it, run it, learn from it.

One canvas takes you from a blank graph to a running instrument you can share — the same engine that powers the editor and every embed.

BUILD

Wire the whole chain

Drag PRBS, FIR, mixers, channel models, CFAR and beamformers onto the canvas and connect them into a graph. Every block exposes its real parameters.

SIMULATE

It runs as you tune

Your graph compiles to a WebAssembly worker and runs live. Scopes, spectra, constellations, MSO, range-Doppler, range-angle and polar PPI update in real time.

LEARN

Read, fork, embed

Start from curated read-only labs, fork them, and rewire. Drop any lab into a lesson or post as an embed — the reader turns a knob and the math responds.

02 · FEATURED DEMOS

Built for the whole signal chain.

Worked examples ship with the editor — fork, retune, rewire. Every demo is one URL away from a runnable lab.

03 · EMBED

Drop a live lab into any page.

One line of markup turns any course note, textbook or blog post into an interactive station. The reader tunes a knob — the math responds.

Chapter 16 · Pulse Shaping & Inter-symbol Interference

16.4 The root-raised-cosine filter

A practical communications receiver must reject out-of-band noise without smearing energy across symbol boundaries. The root-raised-cosine pulse splits the matched-filter response symmetrically between transmitter and receiver, so the cascade satisfies the Nyquist no-ISI condition at the symbol instants.

hRRC(t) = (1 / √Ts) · ƒ(t, β) (16.7)

The roll-off factor β trades excess bandwidth for time-domain sidelobe suppression. Try sweeping β below and observe the constellation tighten: at β → 0 the pulse approaches a sinc and the spectrum is brick-wall, but the time-domain ringing pays the price elsewhere in the chain.

POTIK QPSK RRC Overview v1 embed.potik.org/bpsk-noise

Fig. 16-4 · Live: QPSK source through AWGN with constellation readout. Resample by reload.

Choosing β = 0.35 is a common compromise in cellular and satellite links. As β rises toward unity the time response is more compact — easier on symbol timing — at the cost of doubled occupied bandwidth.

<!-- companion lab, served from embed.potik.org -->
<iframe src="https://embed.potik.org/bpsk-noise" />