BaroAware

Intrusion detection from air pressure. One module per floor. No line of sight, no microphone, no camera, no cloud.

---

A building is a leaky box. Open a hole in it, and the pressure inside changes — everywhere at once.

That last part is the whole product. At the frequencies involved the wavelength is many times the size of the building, so there is no wave travelling and nothing to localise: the enclosed air behaves as one volume. Open the envelope anywhere and the entire volume responds together — through walls, around corners, into the room where the module sits.

This is not acoustic detection. The module is not listening for a sound arriving from somewhere; it watches the pressure of an enclosed volume change when that volume is breached. It sees a door unlocked quietly with a key just as well as one forced.

---

Why this is not already everywhere

Measuring the pressure is the easy half. The other half is that wind against a façade produces swings larger than the event you are looking for. So does a ventilation system starting up. In amplitude, the signal-to-noise ratio is below one.

That kills the obvious approach outright. There is no threshold that catches a window and ignores the weather — not a cleverer threshold, not a sharper filter, not a different band. The two are separated by the shape of the disturbance in time and frequency, not by its size.

So it is learned, not written

BaroAware runs a convolutional neural network trained on real recordings from an occupied building — days and nights, in wind and rain, with people living normally inside. It runs entirely on the microcontroller. No cloud, no gateway, no subscription.

What the module sees

Nobody had to tell the module those two moments were different from the rest. That is the part that took the field data.

---

What that buys the installer

• Nothing to aim. No orientation, no coverage cone, no dead angles, no lens to keep clean. It is a scalar measurement — direction does not exist.
• Works in the dark, through smoke, behind furniture. There is no optical path to obstruct, because there is no optical path.
• One device per connected volume, not one per frame. In our own validation a single module covers ≈140 m² (≈330 m³).
• It cannot record anyone. Not “does not” — cannot. There is no microphone and no camera on the board.

---

BA-CORE-01 — the module

Size	24 × 24 mm
Supply	3.3 V only — all 5 V circuitry stays on the carrier board
Interface	UART, plus two logic outputs: ALARM and TROUBLE
Supply current	approximately 11 mA
Product code	BA-CORE-01

It connects to whatever the integrator already has: an existing alarm panel, an ESP32 or Raspberry Pi, a PLC, a fieldbus node. The module decides on board; the host only has to listen.

---

What it does not do

One limitation, stated plainly: the module tells you that something was opened — not which. If you need to know which window, you still need a contact on that window. BaroAware tells you to go and look, and it does that from one point for the whole volume.

It complements an alarm system. It does not replace door contacts or motion detectors; it covers a class of entry those miss.