System For Giving Intelligibility Feedback To A Speaker

• US 20090012794A1
• Filed: 02/08/2007
• Published: 01/08/2009
• Est. Priority Date: 02/08/2006
• Status: Abandoned Application

• Current Assignee: Embedded Acoustics B.V.
• Original Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Inventors: van Wijngaarden, Sander Jeroen, Verhave, Jan Adrianus
• Application Number:
  US12/278,839
• Publication Number:
  US 20090012794A1
• Time in Patent Office: Days
• US Class Current: 704/270
• CPC Class Codes: G10L 25/48 specially adapted for particular use
• CPC Class Codes: H04R 2420/07 Applications of wireless loudspeakers or wireless microphones
• CPC Class Codes: H04R 29/007 for public address systems public address systems per se H04R27/00
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

System for giving intelligibility feedback to a speaker (1), speaking for an audience (2), comprising a first microphone (3) at the speaker'"'"'s side and a second microphone (4) at the audience'"'"'s side. Both microphones are connected to processing means (5) which are arranged to compute an intelligibility value based on both microphones'"'"' signals. Signalling means (6), preferably at the side of the audience, are arranged to generate an intelligibility feedback signal depending on the calculated intelligibility value. The signalling means being arranged to generate said intelligibility feedback signal in an optical form, visible for the speaker concerned. Wireless connection means (19) may interconnect the microphones, the processing means and the signalling means.

Claims

1. A system for giving intelligibility feedback to a speaker, speaking for an audience, comprising:

a first microphone at the speaker'"'"'s side

a second microphone at the audience'"'"'s side, said first microphone and said second microphone being connected to a processing module arranged to compute a real-time or nearly real-time speech transmission index value based on a signal from said first microphone and a signal from said second microphone; and

a signaling module connected to said processing module and arranged to convey an intelligibility feedback signal to the speaker when said speech transmission index value lies within a certain range or to generate an intelligibility feedback signal when said speech transmission index value lies outside a certain range.

2. The system according to claim 1, said signaling module being arranged to generate said intelligibility feedback signal in an optical form, visible for the speaker.

3. The system according to claim 1, said signaling signaling module being located at the side of the audience.

4. The system according to claim 1, said signalling signaling module being located at the side of the speaker.

5. The system according to claim 3, comprising a wireless connection network, arranged to interconnect, at least in part, the processing module, the first microphone, the second microphone and the signaling module.

6. The system according to claim 1, the processing module being arranged to estimate or calculate a speech transmission index value from a Modulation Transfer Function (MTF) using a cross spectrum between the signal received by the first microphone and the signal received by the second microphone, said cross spectrum being standardized with the auto spectrum of the signal from the first microphone or a modulus of the signal from the first microphone.

7. The system according to claim 6, wherein the Modulation Transfer Function is phase-weighted by detecting a phase difference of said cross spectrum and counting only those parts of the signals from the first and second microphones which are in phase within a predetermined phase difference value.

8. The system according to claim 7, wherein the transfer function MTF is expressed as

9. The system according to claim 7, wherein the phase weight function w is expressed as:

10. The system according to claim 1, wherein said intelligibility feedback signal is further calculated as a function of a primary intelligibility value based on an intelligibility analysis of the first microphone signal;

and said calculated speech transmission index value.

11. The system according to claim 6, the MTF being calculated for modulation frequencies of 1 to 3 Hz and in the octave bands of 500 Hz to 2 kHz.

12. The system according to claim 6, the processing module being arranged to fit the measured enveloping spectra to an anticipated form and to control the generation of said intelligibility feedback signal in dependency of the fitting error.

13. The system according to claim 1, the processing module being arranged to control generation of said intelligibility feedback signal in dependency of a signal level output by the first microphone or the second microphone.

14. The system according to claim 4, comprising wireless connection means, arranged to interconnect, at least in part, the processing means, the first microphone, the second microphone and the signaling module.