Physics-based scintillations for outdoor sound auralization

Area of Science:

• Acoustics
• Atmospheric Physics
• Signal Processing

Background:

• Sound propagation in the atmosphere is affected by turbulence, causing amplitude and phase fluctuations.
• This phenomenon, known as acoustic scintillation, impacts the realism of synthetic audio.
• Current auralization techniques may not fully account for these atmospheric effects.

Purpose of the Study:

• To propose a physics-based formulation for modeling log-amplitude and phase fluctuations of sound in turbulent atmospheres.
• To provide a method applicable to both slanted and vertical sound propagation.
• To enhance the realism of simulated sounds from elevated noise sources.

Main Methods:

• Utilizing spatial correlation functions for log-amplitude and phase fluctuations of spherical waves.
• Applying the von Kármán spectrum to model atmospheric turbulence.
• Employing similarity theories for atmospheric turbulence modeling.

Main Results:

• A physics-based model for acoustic scintillation was developed.
• The model successfully simulates sound propagation in turbulent atmospheres for various scenarios.
• Demonstrated applicability to tonal and broadband noise through audio file examples.

Conclusions:

• The proposed method accurately models acoustic scintillation for realistic sound simulation.
• This formulation is valuable for improving auralization techniques for elevated noise sources.
• The physics-based approach offers a robust framework for understanding sound propagation in turbulent air.