RadioBeat

Feel every beat.
Touch nothing.

A contactless monitor that reads your heartbeat from the WiFi already in your room, and quietly watches for the rhythms that matter, while you sleep.

Explore the live demo See how it works
01 / Signal

It begins with the WiFi already in your room.

02 / Reflection

Your heartbeat bends those waves, ever so slightly.

03 / Capture

RadioBeat reads that flicker, twenty times a second.

04 / Reconstruct

And rebuilds your pulse. From thin air.

Nothing to  wear. charge. remember. touch.

The best health sensor is the one you never have to think about.

Live demo

See what it sees.

A simulation of what RadioBeat reconstructs from WiFi reflections. A beat-to-beat heart trace, breathing rhythm, and live frequency breakdown, pulled from the room without touching anyone. Flip the switch to watch the rhythm turn irregular.

RECNODE A ⇄ NODE BCSI 20 Hz · 802.11n
00:00:00
Heart trace · reconstructedLead: WiFi-CSI
Frequency spectrum0 – 3 Hz
■ Breathing 0.2–0.4 Hz · filtered out■ Heart 0.8–2 Hz · kept
62
BPM
NORMAL SINUS
Breathing14/min
Variability42ms
Signal quality
Irregular rhythm detected. Beat-to-beat timing has turned irregularly irregular, a pattern consistent with atrial fibrillation. In a real deployment, this is where an alert would be raised.
Sinus
Simulate AFib
DEMONSTRATION ONLY · NOT A MEDICAL DEVICE

Why it matters

The most dangerous heartbeat
is the one nobody feels.

Atrial fibrillation is an irregular rhythm that often comes and goes in silence, frequently at night. It can sharply raise the risk of stroke, yet many people never notice a single episode.

0
higher stroke risk associated with untreated atrial fibrillation
0
of AFib episodes estimated to be silent, with no symptoms
1 in 3
estimated lifetime risk of developing atrial fibrillation

// Widely cited public-health estimates, shown for context and illustration.

Under the hood

Built from small, everyday parts.

No exotic radar. No medical hardware. Just cheap, off-the-shelf WiFi chips and open signal processing.

CSI amplitude · subcarriers × time
LIVE STREAM
64 SUBCARRIERS · 40 Hz
LowHigh
ESP32

A common WiFi chip reads CSI

The receiver pulls Channel State Information straight off the radio. No special hardware required.

Band-pass filtering

Carves the heart band away from breathing.

~$20 of parts

A transmitter and a receiver. Two ordinary WiFi chips, about $20 for the pair.

Live web dashboard

A lightweight browser dashboard shows the reconstructed rhythm in real time, exactly like the console above.

Always on, always quiet

It runs in the background around the clock, through the dark, with nothing for you to remember.

 RadioBeatTypical wearable
Something to wearNoneRequired
Nightly chargingNot neededOften
Works while asleepAlways onIf worn
Senses the whole roomYesPer wrist
Runs in the darkYesYes

Build sprint

Where the build actually is.

Six weeks, from a problem statement to a working prototype. Breathing detection comes first because it is the reliable win. The heartbeat is the hard part, and it is built on top.

Week 01

Problem & research

Done
Week 02

Two nodes talking

Done
Week 03

Breathing detected

Done
Week 04

Heartbeat extracted

Done
Week 05

Irregular-rhythm alert

Done
Week 06

Validate & demo

Done

Try the live monitor → The actual app, running on demo data, no hardware needed.

// Six-week sprint complete • breathing measured to within 0.5 breaths/min against known ground truth • AFib screening with five false-alarm guards • heart rate characterised: median error 2.7 BPM, still experimental • live web monitor with accounts.

Being straight about it

What it can do,
and what it can't.

RadioBeat senses movement, not electricity. Knowing exactly where that line sits matters more than pretending it isn't there.

What it can do

  • Screen for irregular beat-to-beat timing, one of the main signs of AFib, and refuse to judge when the heartbeat signal is not clean enough.
  • Measure breathing rate to within about half a breath a minute in testing, with nothing worn.
  • Run in the dark, all night, with nothing to charge or remember.
  • Tell someone to go and get properly checked.

What it can't do

  • Replace an ECG. An ECG reads the heart's electrical signal through electrodes. This reads chest movement, so there is no P wave to record.
  • Diagnose anything. That takes a doctor and a proper test. This only raises a flag.
  • Cope with a busy room. Someone walking past shifts the signal far more than a heartbeat does.
  • Give a reliable heart rate every time. One antenna resolves chest movement to about 1 mm and a heartbeat moves it about 0.45 mm. Averaging over four minutes brings the median error to 2.7 BPM, but roughly a third of readings are still well off.
  • Separate two people breathing at the same rate. Their signals merge into one.

It is a prompt to go get checked. Not a verdict.

Health monitoring
that disappears into the room.

RadioBeat is an early prototype exploring how the WiFi already around us could quietly watch over the rhythms that matter most.

Replay the live demo

A project by Adhvik Mahesh · Grade 9 · GIIS PG Singapore
adhvikmahesh29@gmail.com