MEMS-BASED AUDIO SPEAKER SYSTEM USING SINGLE SIDEBAND MODULATION

摘要

Techniques described herein generally include methods and systems related to a MEMS-based audio speaker system configured with multiple speaker devices to generate an audio signal that is substantially without a high-band ultrasonic signal. Energy may be transferred to a low frequency sideband of the audio signal output and substantially eliminated from the high frequency sideband of the audio signal by passing an acoustic carrier signal through two different modulators. One modulator may implement a first modulation function on the acoustic carrier signal to generate a first audio signal, where the first modulation function may be based on a target acoustic output signal for the MEMS-based audio speaker system. The second modulator may implement a second modulation function on the acoustic carrier signal to generate a second audio signal, where the second audio signal may be the Hilbert transform of the first audio signal.

主权项

1. A speaker apparatus, comprising:
a first speaker device comprising a first oscillation element configured to generate a first ultrasonic acoustic signal along a first directional path and a second oscillation element configured to modulate the first ultrasonic acoustic signal such that a first acoustic signal is generated; and a second speaker device comprising a third oscillation element configured to generate a second ultrasonic acoustic signal along the first directional path and a fourth oscillation element configured to modulate the second ultrasonic acoustic signal such that a second acoustic signal is generated that is a linear derivation of the first acoustic signal and is a different acoustic signal than the first acoustic signal, wherein the first speaker device and the second speaker device are each contained in a volume with at least one dimension smaller than a wavelength of the first ultrasonic acoustic signal.