Microsemi Semiconductor (u.s.) Inc.

Zarlink Semiconductor Limited

Microsemi Semiconductor Ulc

Microsemi Semiconductor Limited

Dean Morgan

Kamran Rahbar

Gary Q Jin

Eric Bass

David Colby

Michael C Gallagher

Siddharth Raghunandan

Jim Van Buskirk

Ivan Acosta

Michael Gallagher

An acoustic delay measurement apparatus measures an audio delay introduced by an audio system. A programmable delay buffer, which introduces a programmable delay into the audio stream, receives an audio stream from an audio source and outputs a reference signal representing the audio stream. An adaptive filter is responsive to the reference signal to generate an estimate signal to match on convergence of the adaptive filter an audio signal output by the audio system, which is the audio stream delayed by an amount representative of the audio delay introduced by the audio system. A processor including a coefficient analysis block reads coefficients in the adaptive filter after convergence, computes a delay introduced into said estimate signal by the adaptive filter, and adds the computed delay to the programmable delay buffer to provide a measurement of the audio delay.

Acoustic delay measurement using adaptive filter with programmable delay buffer

A glass breakage detection method, constituted of: receiving a plurality of audio samples; estimating low frequency power values of the received plurality of audio samples; estimating wide band power values of the received plurality of audio samples; responsive to the estimated wide band power values, determining an amplification value; responsive to the estimated low frequency power being greater than a predetermined threshold, amplifying a function of the received plurality of audio samples by the determined amplification value; comparing the amplified function with a predetermined function of sound of breaking glass; and outputting an indication of the comparison.

Glass breakage detection system

A method of reducing noise in an environment where the noise source is in a fixed location relative to a pair of microphones, such as in a camera with a zoom motor, involves receiving signals x(t), x(t) from the respective microphones, and filtering each of the signals x(t), x(t) with respective first and second linear filters having filter coefficients obtained by computing eigenfilters corresponding to data samples from the respective microphones for noise only and signal only conditions.

Motor noise reduction circuit

To reduce noise in an input signal that may contain speech, first an estimate of the noise level in the signal is obtained. The level of the input signal is then compared with the noise level estimate signal to determine whether speech is dominant. Less aggressive noise reduction is applied to the input signal when speech is dominant than when only noise is present.

Low complexity noise reduction method

Growing community of inventors

Kanata, Canada

Dean Morgan