A plane wave generation method by wave number domain point focusing.

Area of Science:

• Acoustics
• Wave Physics
• Signal Processing

Background:

• Generating precise plane waves is crucial for acoustic testing and research.
• Existing methods can be complex and require extensive calibration.
• Controlling wave-fields efficiently remains an active area of research.

Purpose of the Study:

• To present a new method for generating plane waves using loudspeaker arrays.
• To demonstrate the effectiveness of spherical harmonics for wave-number concentration.
• To provide a computationally efficient approach for deriving loudspeaker input signals.

Main Methods:

• Utilizing a phased array of loudspeakers to concentrate the wave-number spectrum.
• Employing spherical harmonics expansion for wave-field analysis.
• Using a limited number of measurement points on a spherical surface for characterization.

Main Results:

• Achieved a near-plane wave-field with a concentrated wave-number spectrum.
• Demonstrated the method's efficacy with numerical examples under various loudspeaker assumptions.
• Showcased that input signals can be derived without matrix inversion.

Conclusions:

• The described method offers an efficient and approximate way to generate plane waves.
• The approach is potentially useful for various acoustic applications.
• Spherical harmonics provide a robust framework for wave-field synthesis.