Voice pitch modification to increase command and control operator situational awareness

• US 9,620,140 B1
• Filed: 01/12/2016
• Issued: 04/11/2017
• Est. Priority Date: 01/12/2016
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Linnig, Michael J.
• Primary Examiner(s): Baker, Charlotte M
• Application Number:
  US14/993,916
• Time in Patent Office: 455 Days
• Field of Search: 704275, 704278, 725 10, 725 12
• CPC Class Codes: G10L 21/013 Adapting to target pitch
• CPC Class Codes: G10L 21/0364 for improving intelligibility
• CPC Class Codes: G10L 25/24 the extracted parameters being the cepstrum
• CPC Class Codes: G10L 25/90 Pitch determination of speech signals

Abstract

A system for providing voice audio to an operator. The system includes: one or more audio inputs for receiving at least two received voice audio signals; a processing unit, a digital to analog converter, and a loudspeaker. The processing unit is connected to the one or more audio inputs, and configured to: adjust the pitch of a first voice audio signal of the at least two received voice audio signals to form a first adjusted voice audio signal; and combine the first adjusted voice audio signal with at least one other received voice audio signal or adjusted voice audio signal to form a composite audio signal. The pitch in the audio allows the listener to disambiguate one or more speakers or conveys to the listener attributes such as urgency or location information.

Claims

1. A system for selectively altering voice audio provided to an operator for identification of specific voices, the system comprising:

one or more audio inputs for receiving at least two received voice audio signals;

a processing unit connected to the one or more audio inputs, the processing unit being configured to;

adjust the pitch of a first voice audio signal of the at least two received voice audio signals to form a first adjusted voice audio signal; and

combine the first adjusted voice audio signal with at least one other received voice audio signal or adjusted voice audio signal to form a composite audio signal;

a digital to analog converter configured to receive the composite audio signal from the processing unit and to convert it to analog form, to form an analog composite audio signal; and

a first transducer configured to receive the analog composite audio signal and to convert the analog composite audio signal to an acoustic signal for the operator.

2. The system of claim 1, wherein the adjusting of the pitch of the first voice audio signal comprises:

estimating a pitch frequency of the first voice audio signal;

generating filter parameters corresponding to characteristics of the first voice audio signal;

adjusting the pitch frequency to form an adjusted pitch frequency;

generating a square wave at the adjusted pitch frequency; and

filtering the square wave with a filter having the filter parameters.

3. The system of claim 2, wherein the filter is an infinite impulse response filter and the filter parameters are coefficients of the infinite impulse response filter.

4. The system of claim 2, wherein the estimating of the pitch frequency of the first voice audio signal comprises calculating a cepstrum of the voice audio signal.

5. The system of claim 2, wherein the adjusting of the pitch frequency comprises multiplying the pitch frequency by a factor having an absolute value greater than 1.1 and less than 1.2.

6. The system of claim 1, further comprising a second transducer, wherein the system is configured to drive the first transducer and the second transducer with a stereo signal, corresponding to the first adjusted voice audio signal, with a stereo spatial position at least 30 degrees away from center.

7. The system of claim 6, wherein the system is system is configured to drive the first transducer and the second transducer with a stereo signal, corresponding to the first adjusted voice audio signal, with a stereo spatial position at least 30 degrees away from center, by driving one transducer, of the first transducer and the second transducer, with a first signal, and driving the other transducer, of the first transducer and the second transducer, with a second signal, the first signal having an amplitude greater than that of the second signal.

8. The system of claim 1, wherein the adjusting of the pitch of the first voice audio signal comprises:

taking a Fourier transform of the first voice audio signal to form a frequency-domain representation of the first voice audio signal;

adjusting the frequency-domain representation of the first voice audio signal to form an adjusted frequency-domain representation of the first voice audio signal; and

taking an inverse Fourier transform of the adjusted frequency-domain representation of the first voice audio signal.

9. The system of claim 8, further comprising a second transducer, wherein the system is configured to drive the first transducer and the second transducer with a stereo signal, corresponding to the first adjusted voice audio signal, with a stereo spatial position at least 30 degrees away from center.

10. The system of claim 9, wherein the system is system is configured to drive the first transducer and the second transducer with a stereo signal, corresponding to the first adjusted voice audio signal, with a stereo spatial position at least 30 degrees away from center, by driving one transducer, of the first transducer and the second transducer with a first signal, and driving the other transducer, of the first transducer and the second transducer, with a second signal, the first signal having an amplitude greater than the amplitude of the second signal.

11. A method for selectively altering voice audio provided to an operator for identification of specific voices, the method comprising:

receiving, at one or more audio inputs, at least two received voice audio signals;

adjusting the pitch of a first voice audio signal of the at least two received voice audio signals to form a first adjusted voice audio signal;

combining the adjusted voice audio signal with at least one other received voice audio signal or adjusted voice audio signal to form a composite audio signal; and

transmitting the output signal to an digital to analog converter.

12. The method of claim 11, wherein the adjusting of the pitch of a voice audio signal comprises:

estimating a pitch frequency of the first voice audio signal;

generating filter parameters corresponding to characteristics of the first voice audio signal;

adjusting the pitch frequency to form an adjusted pitch frequency;

generating a square wave at the adjusted pitch frequency; and

filtering the square wave with a filter having the filter parameters.

13. The method of claim 12, wherein the filter is an infinite impulse response filter and the filter parameters are coefficients of the infinite impulse response filter.

14. The method of claim 12, wherein the estimating of the pitch frequency of the first voice audio signal comprises calculating a cepstrum of the first voice audio signal.

15. The method of claim 12, wherein the adjusting of the pitch frequency comprises multiplying the pitch frequency by a factor having an absolute value greater than 1.1 and less than 1.2.

16. The method of claim 11, further comprising transmitting an output of the analog to digital converter to a transducer.