Dynamic Sound Delivery With Noise-Adaptive Multi-Band Gain Control

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Solution Overview

Problem

Ambient noise interferes with audio playback in two-way communication systems and audio playback systems, causing masking issues where loud noise covers up the sound signal, and existing technologies fail to effectively compensate for noise conditions remotely.

Innovation Solution

A dynamic sound delivery system that uses a processor to detect ambient noise and apply selective gain control to the playback signal, utilizing multi-band dynamic range processing and compression to adjust the signal's dynamic range based on noise conditions, ensuring intelligibility in noisy environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ambient noise is present at the listener's location, then the noise masks the playback signal making speech unintelligible, but increasing the signal gain to overcome masking may cause distortion or loss of signal detail

Engineering Contradiction:
Improvespeech intelligibilityVSAvoidmasking effect
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies different gain adjustments to different frequency bands of the playback signal based on the spectral characteristics of the ambient noise. Instead of uniformly increasing all frequencies, the system selectively boosts specific frequency ranges where masking occurs, preserving signal quality while improving intelligibility in noisy conditions

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The system dynamically adjusts the gain of the playback signal in real-time based on continuously monitored ambient noise conditions. The gain control responds to changing noise levels and spectral content, allowing the system to adapt to varying acoustic environments and maintain optimal speech intelligibility

Inventive Principle:
Principle #15Dynamics

2Reliability

If the talker increases voice level to compensate for noise, then speech intelligibility improves, but the talker cannot know the noise conditions at the listener's remote location

Engineering Contradiction:
Improvespeech intelligibilityVSAvoidnoise condition awareness
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The system implements a feedback mechanism where the listener's device monitors ambient noise conditions and communicates this information back to the talker's device. This allows the talker to adjust their voice level or the system to apply appropriate gain compensation based on actual noise conditions at the listener's location, resolving the information asymmetry problem

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent introduces an intermediary system (the communication device with noise monitoring and processing capabilities) that bridges the information gap between talker and listener. The intermediary measures noise conditions, processes the playback signal with appropriate gain control, and delivers compensated audio to the listener, eliminating the need for the talker to directly perceive remote noise conditions

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If dynamic gain control is applied to compensate for noise, then speech intelligibility in noisy environments improves, but the system complexity increases

Engineering Contradiction:
Improvespeech intelligibility in noiseVSAvoidgain control processing
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent divides the audio signal into multiple frequency bands and applies independent gain control to each band based on the spectral characteristics of ambient noise. This segmentation allows the system to target specific frequency ranges affected by masking while keeping processing requirements manageable through modular band-by-band adjustment

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2283484B1System and method for dynamic sound delivery
Publication Date: 2015.07.29 DOLBY LABORATORIES LICENSING CORP
  • EP2283484B1 patent drawingFigure 1A~1B
  • EP2283484B1 patent drawingFigure 2~4
  • EP2283484B1 patent drawingFigure 3

AI summary

A dynamic range manipulation system, for use for example in an audio playback system such as a two-way communication system, mobile telephone, MP3 player, and the like, obtains a measure of ambient noise at the playback location and adjusts the gain of the drive signal provided to the loudspeaker based on this measure and based on the audio signal to be played back.