Techniques for range finding for an unmanned aerial system are described. As one example, an unmanned aerial system includes at least one motor to provide propulsion, a piezoelectric acoustic actuator having a resonant frequency, a piezoelectric acoustic sensor having the resonant frequency, and a controller to modulate a fixed amplitude and fixed frequency, at the resonant frequency, carrier wave according to a pseudo-random sequence of bits to produce a modulated wave sequence having a respective section of the carrier wave for each bit of the bits of the pseudo-random sequence having a first value, and a respective section of the carrier wave for each bit of the bits of the pseudo-random sequence having a second value, transmit the modulated wave sequence from the piezoelectric acoustic actuator, receive a reflected wave sequence including a reflection of the modulated wave sequence with the piezoelectric acoustic sensor, determine a delay time between the transmit and the receive of the modulated wave sequence based on the reflected wave sequence received by the piezoelectric acoustic sensor and the modulated wave sequence transmitted by the piezoelectric acoustic actuator, and modify power provided to the at least one motor based on the delay time.

A piezoelectric micro-machined ultrasonic transducer (PMUT) is provided, comprising a dedicated ultrasonic transmitter and at least one separate dedicated ultrasonic receiver on a single common semiconductor die. A plurality of PMUTs may be arranged in a tessellated array. Also disclosed is a system comprising at least one PMUT on a single common semiconductor die, a dedicated ultrasonic transmitter arranged to transmit a first ultrasonic signal and at least one separate dedicated ultrasonic receiver arranged to receive a second ultrasonic signal is also provided. The system further comprises a signal processing subsystem which comprises an analogue domain; a digital domain; a digital to analogue converter; and an analogue to digital converter. The signal processing subsystem is arranged to generate an estimated direct path signal in said digital domain, convert said estimated direct path signal to an analogue estimated direct path signal using said digital to analogue converter, subtract said analogue estimated direct path signal from said second signal to produce a modified received signal and convert said modified received signal to a digital modified received signal using said analogue to digital converter.

An operating method for an ultrasound transceiver device, where the ultrasound transceiver device is alternately and, in particular alternatingly operated in a transmit mode and in a receive mode; subsequently to a transmit mode and/or prior to a receive mode, the ultrasound transceiver device is actively damped by the action of a sequence of counter control pulses; a phase position and/or a damping energy are/is iteratively determined or adapted via a training by a measure of the damping success at least temporarily assuming or approaching an at least locally optimal value.

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.

A vehicle is located on a digital map, with objects being stored in the digital map in a georeferenced manner. From a set of these objects stored in a georeferenced manner in the digital map, which are currently being detected by the environment sensor, the object most distant from the environment sensor is identified and a current sensor range of the environment sensor is determined on the basis of the distance of the environment sensor from the object.

An outside sensor unit includes an outside sensor, a main bracket, a support bracket, a rotation device, and a position adjustment device. The outside sensor detects the outside of a vehicle. The main bracket is attached to a vehicle body. The support bracket supports the outside sensor and is attached to the main bracket. The rotation device has a rotation axis line which is substantially parallel to a roll axis of the vehicle and connects the support bracket and the main bracket together rotatably around the rotation axis line. The position adjustment device is capable of adjusting the relative rotation position between the support bracket and the main bracket around the rotation axis line.

A radar authentication method includes after obtaining output data of a to-be-authenticated radar, a computer device that first invokes a prediction model to obtain predicted data of the to-be-authenticated radar based on the output data of the to-be-authenticated radar, where the prediction model is obtained through training based on output data of a target radar. Then the computer device verifies, based on the predicted data of the to-be-authenticated radar and the output data of the to-be-authenticated radar, whether the to-be-authenticated radar and the target radar are the same radar.

Disclosed are a control method and a control device for an ultrasonic receiving device. The control method includes: determining a target receiver of the ultrasonic receiving device, where the ultrasonic receiving device includes at least two ultrasonic receivers, and the target receiver is one of the at least two ultrasonic receivers on the ultrasonic receiving device that is the nearest to an ultrasonic transmitting device; and controlling a state of each of the at least two ultrasonic receivers on the ultrasonic receiving device based on the determined target receiver. Thus, the ultrasonic ranging error is reduced, and the accuracy of measurement is improved.

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.

A vehicle flow monitoring system for detecting both a car count and direction of movement of vehicles passing a point of interest. The vehicle flow monitoring system generally includes a car counter which may include a microcontroller and a pair of distance sensors. Each of the distance sensors is oriented toward a unique point of interest. Each of the distance sensors includes a threshold distance reading which is used to detect whether a vehicle has passed underneath the car counter. The system may determine direction of travel of the vehicle based on which of the distance sensors is passed by the vehicle first. The microcontroller may assign an Event ID to each time a vehicle passes each of the sensors, with the Event ID being used to identify when and if the vehicle should be counted, or whether a non-vehicle object has passed the car counter.