Ultrasonic equalization and gain control for smart speakers
US11971476B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2021 |
| Grant date | Apr 30, 2024 |
| Priority date | — |
| Expiry date | Jun 30, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/50
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Ultrasonic audio processing circuitry and a method useful in ultrasonic presence detection. An ultrasonic burst generator produces an ultrasonic burst signal at one or more ultrasonic frequencies, and an equalizer equalizes that ultrasonic burst signal according to frequency response characteristics of the speaker and microphone at those ultrasonic frequencies. Driver circuitry drives a speaker with the ultrasonic burst signal, which may be combined with an audible audio signal. An ultrasonic separation filter separates an ultrasonic portion from a signal received at a microphone, and processing circuitry is provided to determine a delay time of an echo corresponding to the ultrasonic burst signal in that separated ultrasonic portion of the received signal. In another aspect, the equalizer equalizes an ultrasonic portion of the signal received at a microphone, according to frequency response characteristics of the speaker and microphone at the ultrasonic frequencies of the burst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.