Method and system for transmitting and/or receiving audio signals with a desired direction

• US 20040114772A1
• Filed: 02/10/2004
• Published: 06/17/2004
• Est. Priority Date: 03/21/2002
• Status: Abandoned Application

• Current Assignee: D-Start Advanced Technologies Limited
• Original Assignee: D-Start Advanced Technologies Limited
• Inventors: Zlotnick, David
• Application Number:
  US10/472,599
• Publication Number:
  US 20040114772A1
• Time in Patent Office: Days
• US Class Current: 381/92
• CPC Class Codes: G10L 25/27 characterised by the analysis technique
• 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: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407

Abstract

A method and system are presented for carrying out at least one of the following: a process of transmitting acoustic signals from an acoustic transmitting array in a desired direction towards a subject location, and a process of receiving acoustic signals propagating in a desired direction from a subject location by an acoustic receiving array. Data indicative of the desired direction is provided and utilized for processing collected signals to be transmitted as acoustic signals through the transmitting array, and/or processing signals collected by the receiving array. The processing is based on a selected wavelet packet transform model. An output signal resulting from the processing is shaped such that maximal energy of the output signal is substantially that of the desired direction.

Claims

1. A method for controlling communication between acoustic devices and a subject location, the method utilizing signal processing by a wavelet packet transform model and being characterized in:

.

(i) processing first digital signals representative of external acoustic signals received by the at least two acoustic receiving devices to identify a desired communication direction associated with the subject location, and using data indicative of the desired direction for optimizing parameters of a selected wavelet packet transform model to be used for controlling the communication between at least two acoustic transmitting devices and the subject location; and

(ii) controlling said communication by processing second digital signals representative of signals that are to be transmitted as acoustic signals through the at least two acoustic transmitting devices, said processing comprising applying to said second digital signals the optimized selected wavelet packet transform model to thereby produce a second digital output signal to operate said at least two acoustic transmitting device, said second digital output signal having an optimal shape with a desired angular distribution of energy in said signal such that a maximal energy component thereof is substantially that of the desired direction, while its energy components associated with directions outside said desired directions are substantially suppressed.

2. The method according to claim 1, comprising controlling receipt by the at least two acoustic receiving devices of the external acoustic signals propagating in the desired direction from the subject location, while substantially preventing receipt of acoustic signals coming from outside said desired direction, said controlling comprising processing of the first digital signals representative of the external acoustic signals received by said at least two receiving devices by applying to said first digital signals the optimized selected wavelet packet transform model to thereby produce a first digital output signal indicative of the received acoustic signals and having an optimal shape such that a maximal energy component thereof is substantially that of the desired direction, while its energy components associated with directions outside said desired direction are substantially suppressed.

3. The method according to claim 1 or 2, comprising dynamically identifying the desired communication direction and optimizing the wavelet packet transform model in accordance with the communication direction.

4. The method according to any one of claims 1 to 3, comprising:

receiving acoustic signals by the at least two acoustic receivers,

analyzing the received acoustic signals to identify whether said received acoustic signals include signals associated with an authorized subject;

upon identifying that the received acoustic signals include signals associated with the authorized subject, processing said received signals to determine direction of the signals coming from the subject, said direction being the desired direction.

5. The method according to any one of preceding claims wherein

actuating reception of the acoustic signals coming from the subject;

processing the received acoustic signals to obtain the data indicative of the desired direction.

6. The method according to claim 4 or 5, wherein said received acoustic signals are voice signals of the authorized subject, the method also comprising storing data indicative of the audio signature of the authorized subject.

7. The method according to claim 5, wherein the actuating of reception of the acoustic signals comprises generating and transmitting a control signal from a vicinity of said at least two acoustic receiving devices to thereby produce a response to said control signal generated by an external unit at the subject location.

8. The method according to any one of preceding claims, wherein said second digital signals to be processed are representative of collected external signals that are received by a communication utility and are to be transmitted through the at least two acoustic transmitting devices in the form of acoustic signals.

9. The method according to any one of preceding claims, wherein the first digital output representative of said first digital signals is used to operate a communication utility to transmit signals indicative of the acoustic signals received substantially from the desired direction.

10. The method according to any one of preceding claims, wherein said processing of the digital signals with the selected wavelet transform model comprises decomposing each of the digital signals into a matrix of sub-signals, each lo being a base function of both frequency and time multiplied by a predetermined coefficient, which characterizes energy of the respective sub-signal, the coefficients being predetermined in accordance with the desired direction, such that the maximal energy of the output digital signal is associated substantially with the desired direction.

11. A system for controlling communication between acoustic devices and a subject location, the system comprising acoustic devices and a processor system connectable to the acoustic devices and operable to process signals with a wavelet packet transform model, the device being characterized in:

(a) said acoustic devices comprises at least two acoustic transmitting devices operable to transmit data indicative of collected digital signals, coming from a communication utility, as acoustic output signals, and at least two acoustic receiving devices operable to receive external acoustic signals and generate digital signals representative thereof;

(b) said processor system is connectable to the communication utility, and comprises a beam forming utility preprogrammed to be responsive to input digital signals representative of external acoustic signals received by the at least two acoustic receiving devices to identify a desired communication direction associated with the subject location, and to use data indicative of the desired direction for optimizing parameters of a selected wavelet packet transform model, and preprogrammed for using the optimized wavelet packet transform model for controlling the communication between said at least two acoustic receiving devices and at least two acoustic transmitting devices and the subject location, by selectively processing with the optimized selected wavelet packet transform model first digital signals representative of external acoustic signals received by the at least two acoustic receiving devices or second digital signals representative of signals that are to be transmitted as acoustic signals through the at least two acoustic transmitting devices, to selectively produce, respectively, a first digital output signal representative of the external acoustic signals to operate the communication utility and a second digital output signal representative of the digital signals coming from the communication utility to operate said at least two acoustic transmitting devices, each of the first and second digital output signals having an optimal shape in accordance with a desired angular distribution of energy in said output signal such that a maximal energy of the output signal is substantially that of the desired direction, while energy components of said signal associated with directions outside the desired direction are substantially suppressed.

12. The system according to claim 11, wherein said processor system comprises a direction finding utility connectable to the at least two acoustic receiving devices and operable to process the digital representation of the received acoustic signals and obtain said data indicative of the desired communication direction and optimize the parameters of the selected wavelet packet transform model.

13. The system according to claim 12, wherein said direction finding utility comprises a data processing and analyzing utility for receiving the digital representation of the external acoustic signals, determining whether said acoustic signals include signals correlating with a predetermined signature, and upon identifying the correlation, locating the direction from which the correlating acoustic signals come and processing the received acoustic signals, to thereby determine the data indicative of the desired direction.

14. The system according to claim 12, wherein said direction finding utility comprises a data processing and analyzing utility for receiving the digital representation of the external acoustic signals, and processing and analyzing said received acoustic signals to locate the direction from which the acoustic signals come, and create a corresponding signature, to thereby enable selecting a corresponding wavelet transform model to be used by said processor to generate the output signal in accordance with the desired direction.

15. The system according to claim 12, wherein said direction finding utility comprises:

a signal transceiver assembly for transmitting a control signal to thereby produce a response to said control signal generated by an external device at the subject location, and for receiving said response; and

a processing and analyzing utility for processing the received response to locate the subject and determine the desired direction.

16. The system according to claim 15, wherein said signal transceiver assembly includes said at least two receiving devices.

17. The system according to claim 15, wherein said signal transceiver assembly includes at least one of said at least two transmitting devices.

18. The system according to any one of claims 11 to 17, wherein said at least two receiving devices are microphones.

19. The system according to any one of claims 11 to 18, wherein said at least two transmitting devices are loudspeakers.

20. The system according to any one of claims 11 to 19, being a part of a computer system, said processor system being connected to a voice operated programming utility.

21. The system according to any one of claims 11 to 19, being a part of an audio set.

22. The system according to claim 11, being a part of a communication system intended for wire- or wireless communication with another communication system through a network.

23. The system according to claim 11, wherein said communication utility is connectable to a communication network.