Tone & Spectrum (Remote)
Pair a phone to use as the speaker and microphone. The phone synthesizes the tone locally; its mic stream is sent here over WebRTC and rendered as a live spectrum.
Enter the 4-digit code shown on the host laptop to use this phone as its speaker and microphone.
Pair your phone
Generating session…
On your phone, open sensingstudio.org/tone-remote and enter this code.
Join a session
Enter the 4-digit code from the host laptop:
Tone (synthesized on phone)
Microphone Spectrum (from phone)
Audio travels via WebRTC (Opus codec). Expect bandwidth roll-off above ~16 kHz and some quantization artifacts versus a direct mic feed.
Doppler Ninja
A near-inaudible carrier (~19 kHz) plays from the phone's speaker. When your hand moves toward or away from the phone, the reflected wave returns shifted in frequency (Δf = 2·v·f/c — about 110 Hz per m/s at 19 kHz). The phone runs the FFT on the raw mic locally and sends just the sideband sums to your laptop over the data channel — so the analysis bypasses the WebRTC Opus codec. The laptop then runs the game and renders the blade.
The carrier plays from the phone, not your laptop — wave your hand 10–40 cm above it. The phone analyzes its own mic, so 19 kHz works (no Opus rolloff to worry about); drop the slider if your phone's speaker can't reach that high. Hold still during calibration.
Sensor Mode
This phone is the speaker and microphone. Your laptop displays the spectrum and controls the tone.
Status
Tap Start to enable mic and connect.
Keep this page open and the screen on. Use headphones if you want to avoid hearing the tone over the mic.
Try a different code
Enter a 4-digit code from the host laptop:
Tone
440 Hz
No tone.