System and method for directionally radiating sound

• US 10,063,971 B2
• Filed: 11/16/2016
• Issued: 08/28/2018
• Est. Priority Date: 05/04/2007
• Status: Active Grant

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Hartung, Klaus
• Primary Examiner(s): Kim, Paul S
• Assistant Examiner(s): SUTHERS, DOUGLAS JOHN
• Application Number:
  US15/352,778
• Publication Number:
  US 20170064452A1
• Time in Patent Office: 650 Days
• Field of Search: 381 86, 381 89, 381392, 381304, 381307, 381 95, 381 96
• CPC Class Codes: G10L 25/78 Detection of presence or absence of voice signals switching of direction of transmission by voice frequency in two-way loud-speaking telephone systems H04M9/10
• CPC Class Codes: H04R 1/025 Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture
• CPC Class Codes: H04R 1/323 for loudspeakers H04R1/34 and H04R1/40 take precedence
• CPC Class Codes: H04R 2203/12 Beamforming aspects for stereophonic sound reproduction with loudspeaker arrays
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 5/02 Spatial or constructional arrangements of loudspeakers
• CPC Class Codes: H04R 5/023 in a chair, pillow
• CPC Class Codes: H04S 2400/11 Positioning of individual sound objects, e.g. moving airplane, within a sound field H04S2420/13 takes precedence
• CPC Class Codes: H04S 2420/03 Application of parametric coding in stereophonic audio systems
• CPC Class Codes: H04S 3/002 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 Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence

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.

Claims

1. An audio system for a vehicle having a plurality of seat positions, said audio system comprising:

respective loudspeaker arrays mounted at each of the 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 said seat position and outputs signals corresponding to the detected speech; and

processing circuitry between the microphone and each said respective loudspeaker array, wherein the processing circuitry receives the signals corresponding to the detected speech from the occupant of the first seat position and drives each of the respective loudspeaker arrays at each of one or more other seat positions of the plurality of seat positions to directionally radiate first acoustic energy corresponding to the detected speech to their respective seat position and to directionally radiate second acoustic energy to the first seat position wherein the processing circuitry 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 at the first seat position, wherein the processing circuitry does not drive the respective loudspeaker array at the first seat position to radiate acoustic energy corresponding to the speech detected from the occupant of the first seat position.

2. An audio system for a vehicle having a plurality of distinct seat positions, said audio system comprising:

a plurality of sources of audio signals;

a respective loudspeaker array mounted at each seat position of the plurality of distinct seat positions and coupled to the plurality of sources so that the audio signals drive the respective loudspeaker arrays to radiate acoustic energy;

wherein a first source of the plurality of sources comprises at least one microphone mounted in the vehicle with respect to a first seat position of the plurality of distinct 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 plurality of filters including a filter between the plurality of sources 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 combined 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 distinct seat positions to a magnitude of second acoustic energy radiated from the respective loudspeaker array at the first seat position to the first seat position so that the filter reduces the magnitude of the first acoustic energy compared to the second acoustic energy; and

processing circuitry between at least the first source of the plurality of sources and the respective loudspeaker arrays that receives the signals corresponding to the detected speech, wherein the processing circuitry outputs signals corresponding to the detected speech from the occupant of the first seat position to drive the respective loudspeaker array for each said other seat position and does not drive the respective loudspeaker array at the first seat position to radiate acoustic energy corresponding to the detected speech from the occupant of the first seat position.

3. The system as in claim 2, wherein the first source of the plurality of sources comprises a plurality of said at least one microphones.

4. The system as in claim 2, comprising a respective sensor in communication with each of the plurality of distinct seat positions so that the sensor outputs signals indicating whether an occupant is present in the seat position,

control circuitry that receives the signals output by the sensors and, responsively thereto, identifies at which seat position an occupant is present;

a respective filter between the first source of the plurality of source and the respective loudspeaker array mounted at each of the plurality of distinct seat positions;

wherein, in response to the signals output by the sensor, the control circuitry selects the respective filters so that each occupied seat position is a first seat position with respect to the other occupied seat positions.