Abstract: The various embodiments described herein include methods, devices, and systems for ultrasonic sensing on electronic devices. In one aspect, a method is performed at an electronic device having memory, one or more processors, a speaker, and a microphone. The method includes, while audibly communicating with a user via the speaker and microphone: (1) sending one or more ultrasound pulses via the speaker; (2) receiving, via the microphone, one or more signals corresponding to the one or more ultrasound pulses; (3) determining positioning of the user based on the one or more received signals; and (4) adjusting one or more parameters of the speaker and/or the microphone based on the determined positioning.

Abstract: An electronic device has memory, one or more processors, a speaker, and a microphone. The device sends a first set of ultrasound chirps at a first rate via the speaker. It receives, via the microphone, a first set of signals corresponding to the first set of ultrasound chirps and being reflected from a person. The device determines based on the first set of signals that the person is in proximity to the electronic device. In accordance with the determination that the person is in proximity to the electronic device, the device sends a second set of ultrasound chirps at a second rate, faster than the first rate. It receives, via the microphone, a second set of signals corresponding to the second set of ultrasound chirps, and identifies a gesture from the person based on the second set of signals.