Multi-loudspeaker playback system for conference call speaker differentiation

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Solution Overview

Problem

Participants in conference calls struggle to distinguish between different remote speakers due to the summation of audio signals by network operators, making it difficult to identify individual speakers, especially in noisy environments like cars.

Innovation Solution

A method using a multi-loudspeaker playback system that processes the received telephone signal to create distinct apparent positions for each remote speaker's audio output, allowing listeners to perceive audio signals as originating from specific positions, enhancing differentiation between speakers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single loudspeaker is used to playback the telephone signal, then the device complexity is low, but the ability to distinguish between different remote speakers deteriorates

Engineering Contradiction:
Improveplayback system complexityVSAvoidspeaker distinction capability
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The audio signal from multiple remote speakers is segmented and assigned to different loudspeakers based on their apparent positions. Each loudspeaker reproduces audio from specific remote speakers, creating spatial separation that helps participants distinguish between different speakers without requiring complex additional processing equipment.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a spatial dimension to the audio playback by distributing sound from different remote speakers across multiple loudspeakers positioned at different locations. This transforms a monophonic playback problem into a spatial audio experience, allowing participants to distinguish speakers based on their apparent positions in the acoustic space.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If audio signals from multiple remote speakers are summed by the network operator, then the transmission efficiency is improved, but the ability to identify individual speakers deteriorates

Engineering Contradiction:
Improvetransmission efficiencyVSAvoidspeaker identification information
Core Design Contradiction:
ProductivityVSLoss of information

Solution Approach 1:

The network operator performs preliminary action by summing the audio signals from multiple remote speakers before transmission, which improves transmission efficiency. The patent then compensates for the loss of speaker identification by using local analysis of the summed signal to determine apparent positions and distribute the audio appropriately across multiple loudspeakers.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces an intermediary processing step at the local playback device that analyzes the summed audio signal to extract apparent position information. This intermediary analysis restores speaker identification capability without requiring the network operator to transmit separate audio streams, thus maintaining transmission efficiency while recovering speaker distinction.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Ease of operation

If hands-free equipment with a loudspeaker is used, then the ease of operation is improved, but the ability to distinguish between remote speakers deteriorates

Engineering Contradiction:
Improvehands-free participation capabilityVSAvoidspeaker differentiation accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The hands-free equipment is enhanced by segmenting the audio output across multiple loudspeakers instead of using a single loudspeaker. This segmentation allows participants to maintain hands-free operation while gaining the ability to distinguish between different remote speakers through spatial audio separation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent merges the hands-free convenience of a single playback device with the speaker distinction capability of multiple loudspeakers. By combining multiple loudspeakers into a coordinated playback system that reproduces audio from different remote speakers at different apparent positions, the system maintains ease of operation while improving speaker differentiation.

Inventive Principle:
Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enables participants to more easily identify and differentiate between remote speakers by spatially separating their audio outputs, improving the clarity and focus during conference calls, even in distracting environments.

Implementation Method 1

processing the received telephone signal to obtain at least two output signals each corresponding to a different one of the at least two remote speaker signals, and playing back the at least two output signals using the multi-loudspeaker playback system, such that for a listener at a predetermined listening position one of the at least two output signals originates from a first apparent position and a second one of the at least two output signals originates from a second apparent position

Methodology Applied
Scientific EffectAcoustic spatialization: Acoustics

Data Source

PatentEP2456184B1Method for playback of a telephone signal
Publication Date: 2013.08.14 HARMAN BECKER AUTOMOTIVE SYST GMBH
  • EP2456184B1 patent drawingFigure 1~2
  • EP2456184B1 patent drawingFigure 3~4
  • EP2456184B1 patent drawingFigure 5~6

AI summary

The invention relates to a method for playback of a telephone signal during a conference call using a multi-loudspeaker playback system (100), comprising the steps of receiving a telephone signal, wherein the telephone signal comprises audio data from a plurality of remote speakers, identifying in the received telephone signal at least two remote speaker signals corresponding to at least two different remote speakers based on the audio data, processing the received telephone signal to obtain at least two output signals each corresponding to a different one of the at least two remote speaker signals, and playing back the at least two output signals using the multi-loudspeaker playback system (100) such that for a listener at a predetermined listening position one of the at least two output signals originates from a first apparent position and a second one of the at least two output signals originates from a second apparent position, different from the first apparent position.