Ultrasound based air-writing system and method

A computing device for motion tracking and text recognition, the computing device comprising:

• a receiver having sensors that record ultrasound waves associated with a gesture;
• an input/output interface configured to receive the ultrasound waves recorded with the receiver;
• and
• a processor configured to
• estimate angle-of-arrival information for the ultrasound waves,
• associate the angle-of-arrival information with the gesture,
• extract features from the gesture, and
• classify the gesture as a specific text character based on the extracted features by comparing the extracted features with known text characters stored in one or more templates.

A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a processor, implement instructions for motion tracking and text recognition, the instructions comprising:

• generating ultrasound waves with a transmitter;
• receiving the ultrasound waves at a receiver, the receiver including sensors that record the ultrasound waves;
• estimating with a processor, angle-of-arrival information for the ultrasound waves;
• associating the angle-of-arrival information with a gesture;
• extracting features from the gesture;
• and
• classifying the gesture as a specific text character based on the extracted features by comparing the extracted features with known text characters stored in one or more templates.