Product directivity models for parametric loudspeakers.

Area of Science:

• Acoustics
• Signal Processing
• Wave Propagation

Background:

• Parametric loudspeakers utilize nonlinear acoustics for focused sound.
• Previous models accurately predicted main and grating lobes but struggled with sidelobes.
• Accurate sidelobe prediction is crucial for optimizing parametric loudspeaker performance.

Purpose of the Study:

• To revisit and improve the product directivity model for parametric loudspeakers.
• To develop modified models that enhance sidelobe prediction accuracy.
• To validate proposed models against experimental and numerical data.

Main Methods:

• Revisiting the theoretical basis of the product directivity model.
• Proposing three modified models: advanced, exponential, and combined product directivity models.
• Incorporating equivalent Gaussian source radii into the models.

Main Results:

• The proposed models demonstrated significantly improved sidelobe predictions compared to the original model.
• All modified models outperformed the original product directivity model by approximately 10 dB in sidelobe prediction.
• The models provide more accurate predictions for difference frequency waves in parametric loudspeakers.

Conclusions:

• The modified product directivity models offer superior accuracy for predicting parametric loudspeaker sidelobes.
• Accounting for Gaussian source radii is key to enhancing the predictive power of these models.
• The findings contribute to more precise design and application of parametric loudspeaker systems.