System and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources

• US 8,447,585 B2
• Filed: 09/06/2007
• Issued: 05/21/2013
• Est. Priority Date: 12/02/1998
• Status: Expired due to Fees

• Current Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Original Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Inventors: Holzrichter, John F., Burnett, Greg C., Ng, Lawrence C.
• Primary Examiner(s): MCFADDEN, SUSAN IRIS
• Application Number:
  US11/899,653
• Publication Number:
  US 20080004861A1
• Time in Patent Office: 2,084 Days
• Field of Search: 704/2
• US Class Current: 704/2
• CPC Class Codes: G01H 1/12 of longitudinal or not specified vibrations
• CPC Class Codes: G01H 3/00 Measuring characteristics of vibrations by using a detector in a fluid G01H7/00, G01H9/00, G01H11/00 take precedence
• CPC Class Codes: G01H 9/00 Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
• CPC Class Codes: G01N 2291/02491 Materials with nonlinear acoustic properties
• CPC Class Codes: G01N 2291/02836 Flow rate, liquid level
• CPC Class Codes: G01N 2291/02872 Pressure
• CPC Class Codes: G06F 18/256 of results relating to different input data, e.g. multimodal recognition
• CPC Class Codes: G06V 40/10 Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
• CPC Class Codes: G10K 11/16 Methods or devices for protecting against, or for damping, noise or other acoustic waves in general G10K11/36 takes precedence
• CPC Class Codes: G10L 15/02 Feature extraction for speech recognition; Selection of recognition unit
• CPC Class Codes: G10L 15/24 Speech recognition using non-acoustical features
• CPC Class Codes: G10L 19/00 Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis in musical instruments G10H
• CPC Class Codes: G10L 21/0272 Voice signal separating

Abstract

A system and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources is disclosed. Propagating wave electromagnetic sensors monitor excitation sources in sound producing systems, such as machines, musical instruments, and various other structures. Acoustical output from these sound producing systems is also monitored. From such information, a transfer function characterizing the sound producing system is generated. From the transfer function, acoustical output from the sound producing system may be synthesized or canceled. The methods disclosed enable accurate calculation of matched transfer functions relating specific excitations to specific acoustical outputs. Knowledge of such signals and functions can be used to effect various sound replication, sound source identification, and sound cancellation applications.

Claims

1. A computer implemented method for identifying an inanimate sound source, comprising the steps of:

directly measuring an excitation function from excitations of the inanimate sound source;

directly measuring an acoustic function from acoustic emissions of the inanimate sound source;

using a computer for calculating a transfer function from the excitation function and the acoustic function;

using said computer for comparing the transfer function to a set of pre-stored transfer functions corresponding to a set of known inanimate sound sources; and

using said computer for identifying the inanimate sound source as one in the set of known inanimate sound sources whose transfer function best matches the transfer function of the inanimate sound source.

2. The method of claim 1 wherein the step of directly measuring an excitation function from excitations of the inanimate sound source further comprises the step of:

directly measuring an excitation function from purposefully induced excitations of the inanimate sound source.

3. A computer implemented system for identifying an inanimate sound source, comprising:

means for directly measuring an excitation function from excitations of the inanimate sound source;

means for directly measuring an acoustic function from acoustic emissions of the inanimate sound source;

a computer, said computer including means for calculating a transfer function from the excitation function and the acoustic function;

said computer including means for comparing the transfer function to a set of pre-stored transfer functions corresponding to a set of known inanimate sound sources; and

said computer including means for identifying the inanimate sound source as one in the set of known inanimate sound sources whose transfer function best matches the transfer function of the inanimate sound source.