METHOD FOR SELF - CALIBRATING A SET OF ACOUSTIC SENSORS, AND CORRESPONDING SYSTEM

摘要

A method for self-calibration of the position of a set of sensors of acoustic signals, in particular microphones, arranged in a region of space (100), comprising: providing in said region of space (100) a set of sources (TW) of acoustic events (EW), in particular transducers designed to generate acoustic waves; measuring times of flight (ti, j) of said acoustic events (EW) between each source (TW) of acoustic events (EW) and each microphone (SW); and reconstructing the positions (xi, yi, ti) of the set of sensors (SW) and the positions (aj, bj, cj) of the sources (TW) of acoustic events (EW) through a maximum-likelihood estimation procedure executed on the basis of said measured times of flight (ti, j). According to the invention, said method further comprises: acquiring times of emission (tE) of said acoustic events (EW); obtaining said times of flight (ti, j) as a function of the respective times of emission (tEj); calculating from said times of flight (ti, j) distances (di, j) between said sources (TW) and said sensors (DW) and arranging them in a matrix of distances (D); and calculating a matrix (X) of estimated positions of the microphones and a matrix (A) of estimated positions of the sources of events via a maximum-likelihood procedure comprising performing a nonlinear least-squares optimization that minimizes a cost function between Euclidean distances of the positions of the sensors (SW) and of the sources (TW) and said calculated distances (di, j).