Patent attributes
A hearing aid system comprising a pair of hearing devices, e.g. hearing aids, worn at the ears of a user receives a target signal generated by a target signal source and transmitted through an acoustic channel to microphones of the hearing aid system. Due to (potential) additive environmental noise, a noisy acoustic signal is received at the microphones of the hearing system. An essentially noise-free version of the target signal is simultaneously transmitted to the hearing devices of the hearing system via a wireless connection. Based on a sound propagation model of the acoustic propagation channel from the target sound source to the microphones of the hearing aid system, and on relative transfer functions representing direction-dependent filtering effects of the head and torso of the user in the form of direction-dependent acoustic transfer functions from a microphone on one side of the head, to a microphone on the other side of the head, a direction-of-arrival (DoA) of the target sound signal relative to the user is determined using a maximum likelihood approach.