US5768398A
Expired / Lapsed
US
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Signal amplification system with automatic equalizer
Assignee: US Philips Corp
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Filing: 1996-04-02
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Granted: 1998-06-16
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Expires: 2016-04-02
Abstract
Abstract A signal amplification system wherein a signal coming from a microphone is applied to a loudspeaker via a signal processing system. The signal processing system includes an estimator for estimating the transfer function from the loudspeaker to the microphone. The equalizer is set to a transfer function that is reciprocal to the transfer function from the loudspeaker to the microphone to equalize the transfer function from the microphone to the listeners. The estimator may include an adaptive filter which has a transfer function that approaches the transfer function from the loudspeaker to the microphone.
Inventors
- 👤 Cornelis P. Janse
- 👤 Patrick A. A. Timmermans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:38
CPC Classifications
H; H03; H03G; H03G5/00; H03G5/16; H03G5/18; H03G5/22; H04; H04R; H04R3/00; H04R3/02; H04R3/04
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
96 words
A signal amplification system comprising a pick-up element, a playback element, and a signal processing system with equalizer for deriving an output signal for the playback element exclusively from an input signal coming from the pick-up element, wherein the signal processing system comprises an estimator for estimating a transfer function from the playback element to the pick-up element, and setting means for automatically setting the equalizer transfer function in dependence on the estimated transfer function from the playback element to the pick-up element to obtain a desired transfer function from said pick-up element to a listener.
Claim 2
Dependent Claim
96 words
A signal amplification system comprising a pick-up element, a playback element, and a signal processing system with equalizer for deriving an output signal for the playback element exclusively from an input signal coming from the pick-up element, wherein the signal processing system comprises an estimator for estimating a transfer function from the playback element to the pick-up element, and setting means for automatically setting the equalizer transfer function in dependence on the estimated transfer function from the playback element to the pick-up element to obtain a desired transfer function from said pick-up element to a listener.
Claim 3
Dependent Claim
72 words
The signal amplification system as claimed in claim 1, wherein the estimator for estimating the transfer function from the pick-up element to the playback element comprises an echo canceller with an adaptive filter for suppressing the transfer of the input signal of the playback element to the output of the pick-up element, and the signal processing system comprises a calculator for deriving the equalizer transfer function from the adaptive filter transfer function.
Claim 4
Dependent Claim
89 words
The signal amplification system as claimed in claim 2, wherein the input of the signal processing system comprises a subtractor for calculating a difference signal from the output signal of the adaptive filter and the output signal of the pick-up element, in that the signal processing means are arranged for deriving by an equalization filter the output signal for the playback element from the difference signal and for deriving the input signal of the adaptive filter from a signal that is representative of the input signal of the equalizer.
Claim 5
Dependent Claim
69 words
A signal processing system with equalizer for deriving an output signal from a single input signal, wherein the signal processing system comprises an estimator for estimating a transfer function from a playback element to a pick-up element, and setting means for automatically setting a desired transfer function from said pick-up element to a listener in dependence on the estimated transfer function from the playback element to the pick-up element.
Claim 6
Dependent Claim
69 words
A signal processing system with equalizer for deriving an output signal from a single input signal, wherein the signal processing system comprises an estimator for estimating a transfer function from a playback element to a pick-up element, and setting means for automatically setting a desired transfer function from said pick-up element to a listener in dependence on the estimated transfer function from the playback element to the pick-up element.
Claim 7
Dependent Claim
59 words
The signal processing system as claimed in claim 4, wherein the estimator for estimating the transfer function from the output to the input comprises an echo canceller with an adaptive filter for suppressing the transfer from the output to the input and the setting means are arranged for deriving the equalizer transfer function from the adaptive filter transfer function.
Claim 8
Dependent Claim
79 words
The signal processing system as claimed in claim 5, wherein the input of the signal processing system comprises a subtractor for calculating the difference signal from an output signal of the adaptive filter and the input signal, the signal processing means are arranged for deriving by an equalization filter the output signal for the playback element from the difference signal and for deriving the adaptive filter input signal from a signal that is representative of the equalizer input signal.
Claim 9
Independent Claim
78 words
A method of deriving an output signal for a playback element from an input signal coming from a pick-up element exclusively while utilizing an equalizer, the method including the steps of estimating a transfer function from the playback element to the pick-up element and automatically setting the equalizer transfer function in response to the estimated transfer function from the playback element to the pick-up element to obtain a desired transfer function from said pick-up element to a listener.
Claim 10
Independent Claim
78 words
A method of deriving an output signal for a playback element from an input signal coming from a pick-up element exclusively while utilizing an equalizer, the method including the steps of estimating a transfer function from the playback element to the pick-up element and automatically setting the equalizer transfer function in response to the estimated transfer function from the playback element to the pick-up element to obtain a desired transfer function from said pick-up element to a listener.
Claim 11
Dependent Claim
46 words
The method as claimed in claim 7, and including the steps of suppressing the transfer of the input signal from the playback element to the output of the pick-up element by an adaptive filter and deriving the equalizer transfer function from the adaptive filter transfer function.
Claim 12
Dependent Claim
65 words
Method as claimed in claim 8, and including the steps of calculating a difference signal from an output signal of the adaptive filter and the output signal of the pick-up element, deriving the output signal for the playback element from the difference signal and deriving the input signal of the adaptive filter from a signal that is representative of the input signal of the equalizer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-06-15 | 2001-12-15 | 2002-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-15 | 2005-12-15 | 2006-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-15 | 2009-12-15 | 2010-06-16 | $7700.00 | Window Closed / Lapsed |