A system including a transmitter and a receiver array at a location different from that of a transmitter, virtually divides the receiver array into plural sub-arrays, calculate Doppler coefficients based on movement of a target for the sub-arrays, calculates a velocity vector of a target, by using the Doppler coefficients calculated for the sub-arrays, and display velocity vector of the target.

Techniques for calibrating presence-detection devices to account for various factors that can affect the presence-detection devices' ability to detect movement. Presence-detection devices may detect movement of a person in an environment by emitting ultrasonic signals into the environment, and characterizing the change in the frequency, or the Doppler shift, of the reflections of the ultrasonic signals off the person caused by the movement of the person. However, factors such as environmental acoustic conditions, noise sources, etc., may affect the ability of the presence-detection devices to detect movement. To calibrate for these factors, the presence-detection devices may use a loudspeaker to emit an ultrasonic sweep signal that spans different frequencies in an ultrasonic frequency range. The presence-detection devices may generate audio data using a microphone that represents the ultrasonic sweep signal, and analyze that audio data to determine an optimal frequency range and/or transmission power for subsequent ultrasonic signal transmissions.

An object detection device includes: a transmission/reception unit that has a vibrator capable of transmitting and receiving ultrasound, that causes the vibrator to transmit transmission signals at different timings, and that receives the reception signals returning after being reflected on a circumferentially existing object; an acquisition unit that acquires a first distance to the object, based on a time difference between a transmission timing of a first transmission signal and a reception timing of a first reception signal, and that acquires a relative speed of the object, based on a frequency difference between the first transmission signal and the first reception signal; an estimation unit that estimates a second distance to the object at a transmission timing of a second transmission signal to be transmitted subsequently to the first transmission signal; and an adjustment unit that adjusts the number of waves or a transmission time of the second transmission signal.

In order to estimate the trajectory of a moving wave source, this trajectory estimation device (10) comprises: an acquisition unit (11) that acquires wave motion data based on wave motion detected by a plurality of sensors (100); a generation unit (12) that generates a spectrogram using the wave motion data; an extraction unit (13) that extracts a Doppler shift from the spectrogram; a selection unit (14) that selects, as a sensor pair, two sensors that satisfy a preset selection condition pertaining to the Doppler shift; and an estimation unit (15) that estimates the trajectory of a wave source, which is the source generating the wave motion, on the basis of the positional relationship between the sensors constituting the sensor pair and the relationship of the Doppler shift between the two sensors constituting the sensor pair.

An autonomous vehicle includes audio sensors configured to detect audio in an environment around the autonomous vehicle and to generate audio signals based on the detected audio. A processor in the autonomous vehicle receives the audio signals and compares a time domain or frequency domain representation of the audio signals to a corresponding representation of a known emergency vehicle siren. The comparison causes the processor to output a first determination indicating whether the audio signals are indicative of an emergency vehicle siren. The processor also applies a trained neural network to the audio signals that causes the processor to output a second determination indicating whether the audio signals are indicative of the emergency vehicle siren. If the first determination or the second determination indicates presence of an emergency vehicle siren in the environment around the autonomous vehicle, the autonomous vehicle is caused to perform an action.

A system and method for enhancing visualization of color flow ultrasound is provided. The method includes generating estimated parameter values from filtered ultrasound image data. The method includes applying filter thresholds to the estimated parameter values, wherein the filter thresholds comprise first and second high power rejection thresholds and first and second low power and low velocity rejection thresholds. The method includes applying a transparency map to the estimated parameter values between the first and second high power rejection thresholds and between the first and second low power and low velocity rejection thresholds. The method includes generating a color flow image based at least in part on the estimated parameter values. The method includes presenting the color flow image at a display system.

A survey system including a multibeam echo sounder having a single projector array and a single hydrophone array constructs a multi-component message for ensonifying multiple fans and deconstructs a corresponding message echo for use in analyzing the returns from each fan.

A sonar survey system including a multibeam echo sounder using plural transmit projectors and plural receive hydrophones, wherein beams with associated magnitudes are received such that the largest magnitude beam(s) are identified as characterizing beam(s) and data associated with these characterizing beam(s) is used as a compressed characterization of the ensonified space.

A survey system including a multibeam echo sounder and a beam selector for selecting beams with the largest amplitudes.

A survey system including a multibeam echo sounder having a single projector array and a single hydrophone array constructs a multi-signal message and deconstructs a corresponding multi-signal echo to substantially simultaneously perform multiple survey missions.