US 10,219,083 B2 · Method of localizing a sound source, a hearing device, and a hearing system

Abstract

A hearing system comprising a) a multitude M of microphones, M≥2, adapted for picking up sound from the environment and to provide corresponding electric input signals rm(n), m=1, . . . , M, n representing time, rm(n) comprising a mixture of a target sound signal propagated via an acoustic propagation channel and possible additive noise signals vm(n); b) a transceiver configured to receive a wirelessly transmitted version of the target sound signal and providing an essentially noise-free target signal s(n); c) a signal processor configured to estimate a direction-of-arrival of the target sound signal relative to the user based on c1) a signal model for a received sound signal rm at microphone m through the acoustic propagation channel, wherein the mth acoustic propagation channel subjects the essentially noise-free target signal s(n) to an attenuation αm and a delay Dm; c2) a maximum likelihood methodology; and c3) relative transfer functions dm representing direction-dependent filtering effects of the head and torso of the user in the form of direction-dependent acoustic transfer functions from each of M−1 of said M microphones (m=1, . . . , M, m≠j) to a reference microphone (m=j) among said M microphones, wherein it is assumed that the attenuation αm is frequency independent whereas the delay Dm may be frequency dependent. The application further relates to a method. Embodiments of the disclosure may e.g. be useful in applications such as binaural hearing systems, e.g. binaural hearing aids systems.

Claims20

Dependent claims

A hearing system comprising

a multitude of M of microphones, where M is larger than or equal to two, adapted for being located on a user and for picking up sound from the environment and to provide M corresponding electric input signals rm(n), m=1, . . . , M, n representing time, the environment sound at a given microphone comprising a mixture of a target sound signal propagated via an acoustic propagation channel from a location of a target sound source and possible noise signals vm(n) as present at the location of the microphone in question;
a transceiver configured to receive a wirelessly transmitted version of the target sound signal and providing an essentially noise-free target signal s(n);
a signal processor connected to said number of microphones and to said wireless transceiver,
the signal processor being configured to estimate a direction-of-arrival of the target sound signal relative to the user based on
a signal model for a received sound signal rm at microphone m (m=1, . . . , M) through the acoustic propagation channel from the target sound source to the mth microphone when worn by the user, wherein the mth acoustic propagation channel subjects the essentially noise-free target signal s(n) to an attenuation αm and a delay Dm;
a maximum likelihood methodology;
relative transfer functions dm representing direction-dependent filtering effects of the head and torso of the user in the form of direction-dependent acoustic transfer functions from each of M−1 of said M microphones (m=1, . . . , M, m≠j) to a reference microphone (m=j) among said M microphones,
wherein said attenuation αm is assumed to be independent of frequency whereas said delay Dm is assumed to be frequency dependent.

5 more elements

A method of operating a hearing system comprising left and right hearing devices adapted to be worn at left and right ears of a user, the method comprising

providing M electric input signals rm(n), m=1, . . . , M, where M is larger than or equal to two, n representing time, said M electric input signals representing environment sound at a given microphone location and comprising a mixture of a target sound signal propagated via an acoustic propagation channel from a location of a target sound source and possible noise signals vm(n) as present at the location of the microphone location in question;
receiving a wirelessly transmitted version of the target sound signal and providing an essentially noise-free target signal s(n);
processing said M electric input signals said essentially noise-free target signal;
estimating a direction-of-arrival of the target sound signal relative to the user based on
a signal model for a received sound signal rm at microphone m (m=1, . . . , M) through the acoustic propagation channel from the target sound source to the mth microphone when worn by the user, wherein the mth acoustic propagation channel subjects the essentially noise-free target signal s(n) to an attenuation αm and a delay Dm;
a maximum likelihood methodology;
relative transfer functions dm representing direction-dependent filtering effects of the head and torso of the user in the form of direction-dependent acoustic transfer functions from each of M−1 of said M microphones (m=1, . . . , M, m≠j) to a reference microphone (m=j) among said M microphones,
under the constraints that said attenuation αm is independent of frequency whereas said delay Dm is frequency dependent.

5 more elements

Dependencies are inferred from the claim text.

Method of localizing a sound source, a hearing device, and a hearing system

Life of this patent

Method of localizing a sound source, a hearing device, and a hearing system

Life of this patent

Abstract

Claims20