Masking of pure tones within sound from a noise generating source

• US 8,223,985 B2
• Filed: 04/22/2009
• Issued: 07/17/2012
• Est. Priority Date: 04/22/2009
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (GE Vernova, Inc.)
• Original Assignee: General Electric Company
• Inventors: Loud, Richard Lynn
• Primary Examiner(s): Picardat, Kevin M
• Application Number:
  US12/428,071
• Publication Number:
  US 20100272285A1
• Time in Patent Office: 1,182 Days
• Field of Search: 381/73.1, 381/71.4, 381/71.5, 381/71.14, 381/94.1, 381/94.2, 381/94.3, 704/226
• US Class Current: 381/73.1
• CPC Class Codes: G10K 11/1752 Masking
• CPC Class Codes: H04K 2203/12 for acoustic communication
• CPC Class Codes: H04K 2203/34 involving multiple cooperating jammers
• CPC Class Codes: H04K 3/42 characterized by the control of the jamming frequency or wavelength
• CPC Class Codes: H04K 3/43 characterized by the control of the jamming power, signal-to-noise ratio or geographic coverage area
• CPC Class Codes: H04K 3/45 characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"
• CPC Class Codes: H04K 3/825 by jamming

Abstract

A method and system for masking pure tones within sound generated from a noise generating source. The method includes detecting one or more pure tones within sound being generated from the noise generating source, and generating one or more masking sounds capable of masking only the one or more pure tones detected within the sound.

Claims

1. A method for masking pure tones within sound generated from a noise generating source, the method comprising:

detecting one or more pure tones within sound being generated from the noise generating source; and

generating a masking spectrum that includes sound levels at frequencies in bands that are adjacent to each of the one or more pure tones within the sound wherein the sound levels are at frequencies selected based on respective locations of each of the one or more pure tones.

2. The method of claim 1, wherein generating one or more masking sounds comprises determining a masking spectrum having increased sound levels only at frequencies selected based on a location of each pure tone.

3. The method of claim 2, further comprising:

sensing continuously the sound being generated from the noise generating source and the generated masking sound;

detecting any changes in the sound being generated from the noise generating source when sensing continuously; and

automatically varying the masking spectrum and generating one or more masking sounds based on the varied masking spectrum according to the detected changes.

4. A sound masking system for masking pure tones within sound being generated from a noise generating source, the system comprising:

a signal generation device which receives a selected masking spectrum when one or more pure tones are detected, and generates one or more masking sounds at a volume corresponding to the selected masking spectrum;

at least one amplifier which amplifies the one or more masking sounds; and

at least one speaker operatively connected with the at least one amplifier, which outputs the one or more masking sounds to mask the one or more pure tones detected.

5. The sound masking system of claim 4, wherein the signal generation device varies the masking sound as the selected masking spectrum input into the signal generation device is varied.

6. A sound masking system for masking pure tones within sound being generated from a noise generating source, the system comprising:

at least one sensing device which senses the sound being generated from the noise generating source;

at least one signal generation device which receives feedback from the at least one sensing device, detects one or more pure tones within the sound being generated from the noise generating source and generates a masking spectrum that includes sound levels at frequencies in bands that are adjacent to each of the one or more pure tones within the sound, wherein the sounds levels are at frequencies selected based on respective locations of each of the one or more pure tones;

at least one amplifier which amplifies the one or more masking sounds; and

at least one speaker operatively connected with the at least one amplifier, which outputs the one or more masking sounds to mask the one or more pure tones detected.

7. The sound masking system of claim 6, wherein the at least one sensing device is a microphone.

8. The sound masking system of claim 6, wherein the at least one signal generation device determines a masking spectrum including increased sound levels only at frequencies selected based on a location of each pure tone and generates the one or more masking sounds corresponding to the masking spectrum determined.

9. The sound masking system of claim 8, wherein the at least one sensing device continuously senses the sound being generated from the noise generating source and the one or more masking sounds, and continuously provides feedback to the at least one signal generation device, and the at least one signal generation device automatically varies the one or more masking sounds and volume thereof as the sound being generated from the noise generating source varies.

10. The sound masking system of claim 9, further comprising:

a plurality of sensing devices positioned at different locations around the noise generating source, wherein each sensing device senses sound received from the noise generating source at each respective location and the at least one signal generation device receives feedback from the sensing devices, detects one or more pure tones within the sound and generates one or more masking sounds capable of masking the one or more pure tones within the sound received from the noise generating source at each respective location; and

a plurality of speakers which output the one or more masking sounds toward each respective location.