Methods for reducing noise in optical biological sensors
US-2015382105-A1 · Dec 31, 2015 · US
US8942383B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-8942383-B2 |
| Application number | US-201313753441-A |
| Country | US |
| Kind code | B2 |
| Filing date | Jan 29, 2013 |
| Priority date | May 30, 2001 |
| Publication date | Jan 27, 2015 |
| Grant date | Jan 27, 2015 |
A practical reading order for non-experts. Skip the full description unless you need deep technical detail.
What the patent document calls the invention.
A short plain-language summary of the technical disclosure.
Who owns or filed the patent and who is credited as inventor.
Filing, priority, publication, and grant dates set the timeline.
The legal scope of protection — read this for what is actually claimed.
Technology tags used to group this patent with similar filings.
Prior art links and similar publications in this corpus.
Official abstract text for this publication.
Techniques associated with an acoustic vibration sensor are described, including a first detector that receives a first signal and a second detector that receives a second signal and a third signal, wherein the first signal comprises a skin surface microphone signal, a static equalization filter coupled to the first detector and configured to generate an equalized first signal, a voice activity detector coupled to the first detector, and a wind detector coupled to the second detector, the wind detector configured to correlate the second signal and the third signal and to derive from the correlation a plurality of wind metrics associated with a wind noise, the wind detector is further configured to determine a magnitude associated with the wind noise, to determine whether to suspend an activity of the system, and to determine a duration of time that the magnitude associated with the wind noise exceeds a threshold.
Opening claim text (preview).
What is claimed: 1. A system comprising: a first detector that receives a first signal and a second detector that receives a second signal and a third signal, wherein the first signal comprises a skin surface microphone signal; a static equalization filter coupled to the first detector and configured to generate an equalized first signal; a voice activity detector coupled to the first detector, the voice activity detector generating a voice activity detector signal when the first signal corresponds to voiced speech; and a wind detector coupled to the second detector, wherein the wind detector is configured to correlate the second signal and the third signal received at the second detector and to derive from the correlation a plurality of wind metrics comprising a first wind metric, a second wind metric, and a third wind metric that is associated with a wind noise that is an acoustic disturbance corresponding to at least one of air flow and air pressure in the second detector, the wind detector is further configured to determine a magnitude associated with the wind noise using the first wind metric, to determine whether to suspend an activity of the system using the second wind metric, and to use the third wind metric to determine a duration of time that the magnitude associated with the wind noise exceeds a threshold, wherein exceeding the threshold causes the system to switch from a first state to a second state, wherein the wind detector controls a configuration of the second detector according to the plurality of wind metrics, wherein the wind detector uses the plurality of wind metrics to dynamically control mixing of the first signal and the second signal to generate an output signal for transmission. 2. The system of claim 1 , wherein the static equalization filter is configured to generate the equalized first signal by adjusting a frequency of the first signal to substantially match another frequency of speech captured by a primary microphone in an absence of noise. 3. The system of claim 1 , further comprising an adaptive gain control circuit configured to adjust a gain associated with the equalized first signal to substantially match the root mean square of the equalized first signal. 4. The system of claim 3 , wherein the adaptive gain control circuit is configured to adjust the gain when no wind is present and the voice activity detector indicates a presence of speech. 5. The system of claim 1 , wherein the static equalization filter comprises a plurality of biquad filters. 6. The system of claim 1 , wherein the static equalization filter is configured to filter out a response greater than 1 kiloHertz. 7. The system of claim 1 , further comprising a low-pass filter coupled to the first detector. 8. The system of claim 1 , further comprising a high-pass filter coupled to the second detector. 9. The system of claim 1 , wherein the plurality of wind metrics is configured to dynamically adjust a first response from a low-pass filter and a second response from a high-pass filter. 10. The system of claim 1 , wherein the voice activity detector signal is configured to noise gate the first signal. 11. The system of claim 1 , wherein the plurality of wind metrics comprise a wind index metric characterizing a current wind level relative to a minimum wind threshold under which the wind noise is considered to have a negligible impact on noise suppression and audio intelligibility in a host electronic system. 12. The system of claim 11 , wherein the current wind level represents an average current wind level of the wind noise. 13. The system of claim 11 , wherein the wind detector is configured to estimate a wind frequency response of the wind noise using the wind index metric. 14. The system of claim 1 , comprising a comfort equalizer coupled to the second detector, the comfort equalizer configured to generate a comfort wind component and to add the comfort wind component to one or more audio signals, wherein the comfort wind component provides listener awareness of wind presence. 15. The system of claim 1 , wherein the second detector comprises an acoustic sensor. 16. The system of claim 1 , wherein the second detector comprises two omnidirectional microphones. 17. The system of claim 1 , wherein the wind detector comprises an adaptive filter coupled to the second detector, wherein the wind detector correlates signals by calculating energy of an adaptive filter error.
Damping circuit arrangements for transducers, e.g. motional feedback circuits · CPC title
for preventing acoustic reaction {, i.e. acoustic oscillatory feedback (specially adapted for hearing aids H04R25/453)} · CPC title
Mechanical or electrical reduction of wind noise generated by wind passing a microphone · CPC title
Two microphones, one receiving mainly the noise signal and the other one mainly the speech signal · CPC title
Reduction of ambient noise (active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06) · CPC title
Related publications grouped by family.
Answers are generated from the same data shown on this page.