The techniques and systems herein enable target-velocity estimation using position variance. Specifically, a plurality of detections of a target are received for respective times as the target moves relative to a host vehicle. Based on the detections, two-dimensional positions of the target relative to the host vehicle are determined for the respective times. Based on the positions of the target at the respective times, a first variance is determined for a first dimension of the positions, and a second variance is determined for a second dimension of the positions. Based on the first and second variances, an estimated velocity of the target is calculated. By basing the estimated velocity on the variances of the positions, more-accurate estimated velocities may be generated sooner, thus enabling better performance of downstream operations.

Techniques and apparatuses are described that implement a smart-device-based radar system capable of performing gesture recognition using a space time neural network. The space time neural network employs machine learning to recognize a user's gesture based on complex radar data. The space time neural network is implemented using a multi-stage machine-learning architecture, which enables the radar system to conserve power and recognize the user's gesture in real time (e.g., as the gesture is performed). The space time neural network is also adaptable and can be expanded to recognize multiple types of gestures, such as a swipe gesture and a reach gesture, without significantly increasing size, computational requirements, or latency.

Provided are an ultrasonic fingerprint identification circuit, a driving method thereof, and a display device. The ultrasonic fingerprint identification circuit comprises fingerprint identification units each including an ultrasonic fingerprint identification sensor connected to a first node; a control module connected to a composite signal line, a first control signal line and the first node and configured to provide a reset potential to the first node and to provide a pull-up potential to the first node in response to a first level provided by the composite signal line; a reading module connected to a second control signal line, the first node and a reading signal line, and configured to read a detection signal of the first node. The first control signal line connected to one fingerprint identification unit is reused as the second control signal line connected to another fingerprint identification unit.

Provided are an ultrasonic fingerprint identification circuit, a driving method thereof, and a display device. The ultrasonic fingerprint identification circuit comprises fingerprint identification units each including an ultrasonic fingerprint identification sensor connected to a first node; a control module connected to a composite signal line, a first control signal line and the first node and configured to provide a reset potential to the first node and to provide a pull-up potential to the first node in response to a first level provided by the composite signal line; a reading module connected to a second control signal line, the first node and a reading signal line, and configured to read a detection signal of the first node. The first control signal line connected to one fingerprint identification unit is reused as the second control signal line connected to another fingerprint identification unit.

A method for detecting a moving object in a scene includes providing sampled ultrasonic echo signals from the scene; determining echo envelopes of the sampled ultrasonic echo signals; determining differentials of successive echo envelopes for providing echo envelope differentials; determining the absolute values of the echo envelope differentials; and conducting a classification based on the determined absolute values of the echo envelope differentials for determining a relative movement of the moving object.

This application discloses an object recognition method and apparatus based on ultrasonic echoes performed by a computer device. The method includes: receiving an echo signal reflected by an object and captured by a terminal, the echo signal corresponding to an ultrasonic signal transmitted by the terminal to the object; extracting an ultrasonic echo feature of the echo signal; performing feature dimension conversion on the ultrasonic echo feature to obtain a target dimension feature; and further, performing image translation to obtain object image information corresponding to the object. Compared with image collection using cameras, the transmission of ultrasonic signals and the reception of reflected echo signals are less sensitive to the changes of scenarios. When image collection is not feasible, physical information carried by ultrasonic echoes can be accurately translated into the image of the object to be identified, thereby ensuring the accuracy of object recognition.

This application discloses an object recognition method and apparatus based on ultrasonic echoes performed by a computer device. The method includes: receiving an echo signal reflected by an object and captured by a terminal, the echo signal corresponding to an ultrasonic signal transmitted by the terminal to the object; extracting an ultrasonic echo feature of the echo signal; performing feature dimension conversion on the ultrasonic echo feature to obtain a target dimension feature; and further, performing image translation to obtain object image information corresponding to the object. Compared with image collection using cameras, the transmission of ultrasonic signals and the reception of reflected echo signals are less sensitive to the changes of scenarios. When image collection is not feasible, physical information carried by ultrasonic echoes can be accurately translated into the image of the object to be identified, thereby ensuring the accuracy of object recognition.

The present invention concerns a method and apparatus for the modulation of an acoustic field for providing tactile sensations. A method of creating haptic feedback using ultrasound is provided. The method comprises the steps of generating a plurality of ultrasound waves with a common focal point using a phased array of ultrasound transducers, the common focal point being a haptic feedback point, and modulating the generation of the ultrasound waves using a waveform selected to produce little or no audible sound at the haptic feedback point.

The present invention concerns a method and apparatus for the modulation of an acoustic field for providing tactile sensations. A method of creating haptic feedback using ultrasound is provided. The method comprises the steps of generating a plurality of ultrasound waves with a common focal point using a phased array of ultrasound transducers, the common focal point being a haptic feedback point, and modulating the generation of the ultrasound waves using a waveform selected to produce little or no audible sound at the haptic feedback point.

An underwater detection apparatus is provided. The apparatus may include a transmission transducer, a reception transducer, and processing circuitry. The transmission transducer may transmit a transmission wave. The reception transducer may include a plurality of reception elements that generate a reception signal based on a reflection wave including a reflection of the transmission wave on an underwater target. The processing circuitry may generate a 3D image data that represents an echo intensity of the underwater target based at least in part on the reception signal generated by each reception element, and may set a depth marking on the 3D image data for which a depth is equal to a given depth, by changing an echo intensity color that represents the echo intensity of the 3D image data into a depth color that represents a depth of the 3D image data, the depth color being different from the echo intensity color.