System And Method For Driving A Transducer
AssigneeSonicedge Dk Aps
InventorsHenrik Thomsen, Tore Jørgensen, Niels Marker-Villumsen
Life of this patent
Estimating the term…
Abstract
Techniques described herein generally relate to generating an audio signal with a speaker. In some examples, a speaker device is described that includes a membrane and a shutter and driver device is configured to receive an audio signal, modulate it and generate electric signals to operate the speaker and generate an acoustic audio signal.
Claims22
A driver device for operating a modulated ultrasound speaker wherein the ultrasound speaker includes two or more membranes, and the driver device comprises:
- one or more voltage drivers each configured to provide a voltage signal to one or more membranes and or modulators;
- and
- a controller,
- wherein the controller is configured to receive an audio signal and generate a drive signal for the two or more membranes;
- wherein one drive signal is proportional to sin(2πfct) √{square root over (a(t)+b(t))} and the second drive signal is proportional to cos(2πfct) √{square root over (a(t)+b(t))}.
A method for operating a modulated ultrasound speaker having two or more membranes, the method comprising:
- receiving an audio signal;
- applying a bias to the audio signal;
- calculating a square root function of the biased audio signal;
- generating a first drive signal by multiplying the square root function by a first periodic carrier signal;
- generating a second drive signal by multiplying the square root function by a second periodic carrier signal having a phase difference relative to the first periodic carrier signal;
- providing the first drive signal to a first membrane;
- and
- providing the second drive signal to a second membrane.
Dependencies are inferred from the claim text.