Feedback Canceller in a Hearing Assistance System
AssigneeLegato Audio, Inc.
InventorAnand Parthasarathi
Life of this patent
Estimating the term…
Abstract
A feedback cancelation system for a hearing assistance system is provided. The system comprises an adaptive feedback canceller that receives input of a microphone signal from an array of microphones and estimates an acoustic path from a speaker driver back to the microphone array, wherein the adaptive feedback canceller uses the estimate to remove feedback signals from the speaker driver back to the microphone array. The system also comprises an instability estimator that compares microphone signal energy to speaker driver signal energy, wherein, responsive to the ratio of the speaker driver energy to microphone signal energy exceeding a specified threshold, the instability estimator initiates an across-the-board gain reduction into the adaptive feedback canceller.
Claims20
A feedback cancelation system for a hearing assistance system, the feedback cancelling system comprising:
- an adaptive feedback canceller that receives input of a microphone signal from an array of microphones and estimates an acoustic path from a speaker driver back to the microphone array, wherein the adaptive feedback canceller uses the estimate to remove feedback signals from the speaker driver back to the microphone array;
- and
- an instability estimator that compares microphone signal energy to speaker driver signal energy, wherein, responsive to the ratio of the speaker driver energy to microphone signal energy exceeding a specified threshold, the instability estimator initiates an across-the-board gain reduction into the adaptive feedback canceller.
An eyewear device, comprising:
- a left and right eyewear stem, each comprising:
- a first microphone and a second microphone;
- a speaker;
- an adaptive feedback canceller that receives input of a null beamforming microphone signal from the first and second microphones and estimates an acoustic path from the speaker back to the first and second microphones, wherein the adaptive feedback canceller uses the estimate to remove feedback signals from the speaker back to the first and second microphones;
- an instability estimator that compares microphone signal energy to speaker signal energy, wherein, responsive to the ratio of the speaker signal energy to microphone signal energy exceeding a specified threshold, the instability estimator initiates an across-the-board gain reduction into the adaptive feedback canceller;
- and
- a front face capable of holding a pair of eyewear lenses, wherein the front face lacks an electrical conductor connecting the right and left eyewear stem.
An open ear hearing assistance device, comprising:
- a front face capable of holding a pair of eyewear lenses;
- a left and right eyewear stem connected to the front face, each comprising:
- an array of microphones;
- a speaker;
- an adaptive feedback canceller that removes feedback signals from the speaker back to the array of microphones;
- and
- an instability estimator that compares microphone signal energy to speaker signal energy, wherein, responsive to the ratio of the speaker signal energy to microphone signal energy exceeding a specified threshold, the instability estimator initiates an across-the-board gain reduction into the adaptive feedback canceller, wherein the across-the-board gain reduction is maintained until the adaptive feedback canceller has adjusted to the speaker driver energy.
Dependencies are inferred from the claim text.