VAD Detection Apparatus and Method of Operation the Same

• US 20160064001A1
• Filed: 09/22/2015
• Published: 03/03/2016
• Est. Priority Date: 10/29/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Thomsen, Henrik, Nandy, Dibyendu
• Granted Patent: US 9,830,913 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G10L 15/08 Speech classification or search
• CPC Class Codes: G10L 15/22 Procedures used during a speech recognition process, e.g. man-machine dialogue
• CPC Class Codes: G10L 17/02 Preprocessing operations, e.g. segment selection; Pattern representation or modelling, e.g. based on linear discriminant analysis [LDA] or principal components; Feature selection or extraction
• CPC Class Codes: G10L 19/0204 using subband decomposition
• CPC Class Codes: G10L 2015/088 Word spotting
• CPC Class Codes: G10L 25/21 the extracted parameters being power information
• CPC Class Codes: G10L 25/78 Detection of presence or absence of voice signals switching of direction of transmission by voice frequency in two-way loud-speaking telephone systems H04M9/10
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04W 4/16 Communication-related supplementary services, e.g. call-transfer or call-hold

Abstract

At a processing device, a first signal from a first microphone and a second signal from a second microphone are received. The first signal indicates whether a voice signal has been determined at the first microphone, and the second signal indicates whether a voice signal has been determined at the second microphone. When the first signal indicates potential voice activity or the second signal indicates potential voice activity, the processing device is activated to receive data and the data is examined for a trigger word. When the trigger word is found, a signal is sent to an application processor to further process information from one or more of the first microphone and the second microphone. When no trigger word is found, the processing device is reset to deactivate data input and allowing the first microphone and the second microphone to enter or maintain an event detection mode of operation.

Claims

1. A method detecting voice activity in a micro-electro-mechanical system (MEMS) microphone, the method comprising:

at a digital microphone;

receiving a sound energy from a source;

filtering the sound energy into a plurality of filter bands;

obtaining a power estimate for each of the plurality of filter bands;

based upon each power estimate, determining whether voice activity is detected;

wherein the power estimate comprises an upper power estimate and a lower power estimate;

wherein the microphone includes a transducer and an integrated circuit.

2. The method of claim 1, wherein the filtering utilizes one or more low pass filters, high pass filters and frequency dividers.

3. The method of claim 1, wherein ratios between the upper power estimate and the lower power estimate within the plurality of filter bands are determined, and selected ones of the ratios are compared to a predetermined threshold.

4. The method of claim 1, wherein ratios between the upper power estimate and the lower power estimate between the plurality of filter bands are determined, and selected ones of the ratios are compared to a predetermined threshold.

5. A microphone, the microphone comprising:

a filter bank that is configured to receive a sound energy from a source and filter the sound energy into a plurality of filter bands;

a power tracker module coupled to the filter bank and configured to obtain a power estimate for each of the plurality of filter bands, wherein the power estimate comprises an upper power estimate and a lower power estimate;

a decision module coupled to the power tracker module, the decision module configured to and based upon each power estimate, determine whether voice activity is detected.

6. The microphone of claim 5, wherein the filter bank utilizes one or more low pass filters, high pass filters and frequency dividers.

7. The microphone of claim 5, wherein ratios between the upper power estimate and the lower power estimate within the plurality of filter bands are determined, and selected ones of the ratios are compared to a predetermined threshold.

8. The microphone of claim 5, wherein ratios between the upper power estimate and the lower power estimate between the plurality of filter bands are determined, and selected ones of the ratios are compared to a predetermined threshold.