Bayesian Microphone Array Model Selection for Multi-Source DoA Estimation

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Solution Overview

Problem

Challenges exist in accurately identifying the directions of arrival (DoA) of multiple concurrent sound sources in complex acoustic environments due to variations in the number, location, and characteristics of sound sources, along with interference from fluctuating background noise.

Innovation Solution

A Bayesian framework is employed to estimate the number and direction of arrival of sound sources using a microphone array, involving model selection and parameter estimation through Bayes' Theorem, with specific parametric models selected from a generalized model, and utilizing microphone array architectures like coprime and spherical arrays.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional signal processing methods are used for sound source localization, then the system is simpler to implement, but the accuracy deteriorates in complex acoustic environments with multiple concurrent sound sources and fluctuating background noise

Engineering Contradiction:
Improvedirection of arrival estimation accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the mathematical parameters and models used in signal processing. It employs Bayesian frameworks with multiple parametric models (e.g., Gaussian, Laplace, Student's t-distribution) to represent different acoustic scenarios. By adapting the model parameters based on evidence from the acoustic signal, the system achieves high accuracy in DoA estimation while managing complexity through systematic model selection rather than overly complex fixed architectures.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces dynamic model selection where the system adapts its approach based on the acoustic signal characteristics. The Bayesian evidence is used to dynamically select the most appropriate parametric model from multiple candidates, allowing the system to adjust its complexity and behavior in real-time according to the presence of multiple sources, noise levels, and other environmental factors.

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If the number of sound sources varies in the acoustic environment, then the system must be more adaptable, but the difficulty of detecting and measuring increases

Engineering Contradiction:
Improveadaptability to varying number of sourcesVSAvoiddifficulty of sound source enumeration
Core Design Contradiction:
Adaptability or versatilityVSDifficulty of detecting and measuring

Solution Approach 1:

The system dynamically selects the number of sound sources and their corresponding models based on Bayesian evidence. The model selection process automatically adjusts to the actual number of sources present in the acoustic environment, whether there is one source, multiple sources, or no sources at all. This dynamic adaptation resolves the difficulty of enumeration by making the system's complexity variable rather than fixed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent creates a universal framework that can handle multiple scenarios (single source, multiple sources, noisy environments, quiet environments) within a single unified Bayesian model selection system. The same framework processes all these different cases by selecting the appropriate parametric model, eliminating the need for separate specialized systems for each scenario.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Measurement precision

If multiple parametric models are considered in the Bayesian framework, then the measurement precision improves, but the device complexity increases

Engineering Contradiction:
Improvedirection of arrival estimation accuracyVSAvoidmodel selection complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system uses Bayesian evidence as feedback to automatically select the most appropriate model. The evidence quantifies how well each parametric model explains the acoustic signal, and this feedback information drives the model selection process. This feedback mechanism allows the system to achieve high precision through comprehensive model consideration while managing complexity by automatically discarding unnecessary models based on their performance.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent systematically varies the parameters of multiple parametric models (Gaussian, Laplace, Student's t-distribution with different degrees of freedom) and uses Bayesian evidence to select the optimal parameter set. By organizing this parameter exploration in a structured way and using evidence-based selection, the system achieves high measurement precision without the complexity becoming unmanageable.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS12386007B2Sound source enumeration and direction of arrival estimation using a bayesian framework
Publication Date: 2025.08.12 RENESSELAER POLYTECHNIC INST
  • US12386007B2 patent drawing
  • US12386007B2 patent drawing

AI summary

One embodiment provides a method of sound source enumeration and direction of arrival (DoA) estimation. The method, the method includes estimating, by an enumeration module, a number of sound sources associated with an acoustic signal. The estimating includes selecting a specific parametric model from a generalized model. The generalized model is related to a microphone array architecture used to capture the acoustic signal. The method further includes estimating, by a DoA module, a direction of arrival of each sound source of the number of sound sources based, at least in part, on the selected model. The estimating the number of sound sources and estimating the DoA of each sound source are performed using a Bayesian framework.