Lausanne, Switzerland – Blind people are often required to use their hearing to orient themselves in a room but now Swiss scientists have developed software that makes it possible to "hear" a space with the help of acoustic echoes.
The researchers succeeded in calculating a room's geometry using acoustic signals thanks to technology that could in future be built into smartphones, according the PNAS science magazine. The software could also be used to find out from which exact room a phone call was made.
The algorithm developed at Lausanne's EPFL college makes it possible to measure the dimensions of a room using just a few microphones and an acoustic echo.
"Our software can build a 3D map of a simple, convex room with a precision of a few millimetres," says PhD student Ivan Dokmanic.
The microphones do not even need to be carefully placed as each microphone picks up the direct sound from the source, as well as the echoes arriving from various walls, the student explains.
"The algorithm then compares the signal from each microphone. The infinitesimal lags that appear in the signals are used to calculate not only the distance between the microphones, but also the distance from each microphone to the walls and the sound source."
One experiment was carried out in a test room using four microphones while another involved using the technology to map the complex architecture of Lausanne Cathedral.
Researchers are already using the technology for many applications but foresee many more. "This is only the beginning," according to Dokmanic.