System and method for directionally radiating sound

Patent metadata

Field	Value
Publication number	US-9560448-B2
Application number	US-78046807-A
Country	US
Kind code	B2
Filing date	Jul 19, 2007
Priority date	May 4, 2007
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

An audio system for a vehicle has at least one source of audio signals. A respective directional loudspeaker array is mounted at each seat position and coupled to the at least one source. The at least one source includes a microphone that detects speech from an occupant of the first seat position. Processing circuitry receives signals from the microphone that correspond to the detect speech and drives each second respective loudspeaker array at the other seat positions to radiate acoustic energy corresponding to the detected speech. The processing circuitry processes magnitude and phase of the signals from the microphone to each second directional loudspeaker array so that each second directional loudspeaker array directionally radiates first acoustic energy to the seat position at which the second directional loudspeaker array is located and so that second acoustic energy radiated from the second directional array to the first seat position is less than the first acoustic energy according to a predetermined criteria.

First claim

What is claimed is:

1. An audio system for a vehicle having seat positions, said audio system comprising:
a respective loudspeaker array mounted at each of a plurality of seat positions in the vehicle;
a microphone mounted in the vehicle with respect to a first seat position of the plurality of seat positions so that the microphone detects speech from an occupant of the first seat position and outputs signals corresponding to the detected speech; and
processing circuitry between the microphone and each said respective loudspeaker array, wherein, for the first seat position, the processing circuitry receives the signals corresponding to the detected speech from the occupant of the first seat position and drives a respective loudspeaker array at each of one or more seat positions of the plurality of seat positions other than the first seat position to directionally radiate first acoustic energy corresponding to the detected speech to said one or more other seat position and to directionally radiate second acoustic energy to the first seat position so that the second acoustic energy is less than the first acoustic energy according to a predetermined criteria,
wherein each seat position of the plurality of seat positions is a said first seat position with respect to one or more seat positions other than that first seat position and the system has a plurality of said respective loudspeaker arrays mounted at each seat position of the plurality of seat positions, and wherein, at each said other seat position of the plurality of seat positions with respect to a respective said first seat position, the processing circuitry drives any said respective loudspeaker array with signals that correspond to the detected speech from the occupant of the respective first seat position only if the respective loudspeaker array is aligned between said other seat position and the respective first seat position.

2. A method of providing an audio system in a vehicle having a plurality of seat positions at which are disposed respective loudspeaker arrays configured to radiate acoustic energy to the seat positions at which the respective loudspeaker arrays are disposed and to isolate the other said seat positions of the plurality of seat positions from the acoustic energy, comprising the step of:
providing at least one microphone within the vehicle constructed and arranged to detect speech from an occupant of a first said seat position and output signals corresponding to the detected speech to the respective loudspeaker arrays at each of one or more said seat positions other than the first seat position, and excluding the first seat position, so that acoustic energy radiated by the respective loudspeaker array at said each other seat position corresponds to the detected speech;
providing a respective filter between the microphone and said respective loudspeaker array at said each other seat position, wherein the respective filter processes audio signals from the microphone to its respective loudspeaker array;
defining a respective cost function that compares acoustic energy in the vehicle radiated from said respective loudspeaker array at said each other seat position to the first seat position to acoustic energy in the vehicle radiated from the respective loudspeaker array at the other seat position to the other seat position;
calculating each said respective cost function; and
iteratively modifying each respective filter in response to its calculated cost function toward a predetermined criteria so that the acoustic energy radiated to the first seat position from the loudspeaker array at the other seat position corresponding to the respective filter is below a level that causes audio feedback at the first seat position.

3. The method as in claim 2 , wherein each seat position of the plurality of seat positions is a said first seat position with respect to one or more seat positions other than that first seat position and wherein the audio system comprises a plurality of the at least one microphones constructed and arranged to respectively detect speech from an occupant of each seat position.

4. The method as in claim 2 , wherein each respective filter provides unity gain at the second providing step.

5. A method of operating an audio system in a vehicle having a plurality of seat positions at which are disposed respective loudspeaker arrays configured to radiate acoustic energy to the seat positions at which the respective loudspeaker arrays are disposed and to isolate the other said seat positions of the plurality of seat positions from the acoustic energy, comprising the step of:
providing at least one microphone within the vehicle constructed and arranged to detect speech from an occupant of a first said seat position and output signals corresponding to the detected speech to the respective loudspeaker arrays at each of one or more said seat positions other than the first seat position, and excluding the first seat position, so that acoustic energy radiated by the respective loudspeaker array at said each other seat position corresponds to the detected speech; and
driving said respective loudspeaker array at said each of one or more other seat positions to directionally radiate first acoustic energy corresponding to the detected speech to said one or more other seat positions and to directionally radiate second acoustic energy to the first seat position that is optimized based on descent of a gradient of a cost function that compares the first acoustic energy to the second acoustic energy so that the second acoustic energy is below a level that causes audio feedback,
wherein the audio system comprises a filter between the at least one microphone and at least one speaker element in a said respective loudspeaker array at a said other seat position, wherein the filter processes the signals from the at least one microphone to the at least one speaker element of the respective loudspeaker array so that the filter contributes to a transfer function that relates the signals to the acoustic energy radiated to one or more of the plurality of seat positions from the at least one speaker element, and
implementing a set of coefficients to process the signals to the at least one speaker element so that a ratio of said transfer function between the signals and the acoustic energy radiated from the at least one speaker element to the first seat position and said transfer function between the signals and the acoustic energy radiated from the at least one speaker element to the other seat position meets a predetermined criteria for acoustic isolation.

6. An audio system for a vehicle having seat positions, said audio system comprising:
at least one source of audio signals;
a respective loudspeaker array mounted at each seat position of a plurality of the seat positions and coupled to the at least one source so that the audio signals drive the respective loudspeaker arrays to radiate acoustic energy;
wherein the at least one source comprises at least one microphone mounted in the vehicle with respect to a first seat position of the plurality of seat positions so that the at least one microphone detects speech from an occupant of the first seat position and outputs signals corresponding to the detected speech;
a filter between the at least one source and the respective loudspeaker array mounted at the first seat position that processes the audio signals that drive the respective loudspeaker array at the first seat position and is optimized based on descent of a gradient of a cost function that compares a magnitude of first acoustic energy radiated from the respective loudspeaker array at the first seat position to each other seat position of the plurality of seat positions to a magnitude of second acoustic energy radiated from the respective

Assignees

• Hartung Klaus
• Bose Corp

Inventors

• Hartung Klaus

Classifications

• H04S7/302 Primary

  Electronic adaptation of stereophonic sound system to listener position or orientation (H04S7/301 takes precedence) · CPC title

• H04R5/023

  in a chair, pillow · CPC title

• H04S3/002

  Non-adaptive circuits, e.g. manually adjustable or static, for enhancing the sound image or the spatial distribution (control circuits for electronic adaptation of the sound field H04S7/30) · CPC title

• H04R5/02 Primary

  Spatial or constructional arrangements of loudspeakers · CPC title

• H04R2499/13

  Acoustic transducers and sound field adaptation in vehicles · CPC title