VolAnti

Open-source acoustic drone detection. It hears the propellers, not the radio.

Detection and alert only. No jamming, no interception, no countermeasures, ever.

A 91 mm box with four microphones, an ESP32-S3, an e-paper screen and a LoRa radio. It listens for the harmonic comb a multirotor makes and when it hears one it beeps, flashes red, buzzes, writes the time to a screen that survives a power cut, and tells every other unit on the network.

If you want the short illustrated version, or to watch the detector work on a sound field you control, that is what the website and the simulator are for. This page is the long version, and everything needed to build one is in this repository.

Nearly all drone detection listens for radio. It finds the control link between the pilot and the aircraft, decodes it, and reports where both are. It works well, and it has one hard failure: the drone has to transmit.

A fibre-optic FPV drone does not. It trails a thread of glass back to its operator, video comes down the fibre, control goes up it, and the radio spectrum stays silent. There is nothing to find and nothing to decode.

It is not radar and not a replacement for one. It is a cheap local tripwire for the last few hundred metres that keeps working when the radio picture is empty, and that a school or a farm can build and repair themselves.