In a sonar system using a large array multielement sonar detector to detect reflected signals sent out by a sonar ping generator, the sent out sonar ping generator sends out varying frequency sonar signals during each ping, where the frequency is neither monotonically increasing or monotonically decreasing.

The present disclosure is related to a method and device for measuring a distance and a storage medium. The method for measuring the distance includes determining a distance between a first device and a second device based on a first time difference and a second time difference, where the first time difference is between a time of receiving a first detection signal by the first device and a time of receiving a second detection signal by the first device, and the second time difference is between a time of receiving the first detection signal by the second device and time of receiving the second detection signal by the second device.

Disclosed herein are systems and methods for estimating target ranges, angles of arrival, and speed using optimization procedures. Target ranges are estimated by performing an optimization procedure to obtain a denoised signal, performing a correlation of a transmitted waveform and the denoised signal, and using a result of the correlation to determine an estimate of a distance between the sensor and at least one target. Target angles of arrival are estimated by determining ranges at which targets are located, and, for each range, constructing an array signal from samples of received echo signals, and using the array signal, performing another optimization procedure to estimate a respective angle of arrival for each target of the at least one target. Doppler shifts may also be estimated using another optimization procedure. Certain of the optimization procedures use atomic norm techniques.

A method and an apparatus for space status detection based on acoustic chirp signals are provided. The method includes following steps. One of a plurality of acoustic chirp signals is transmitted into a space respectively at a plurality of different time points. A plurality of acoustic waves that are the transmitted acoustic chirp signals varied in the space are sequentially received to generate a plurality of acoustic spatial response signals, and a plurality of space features of the space are obtained based on the acoustic spatial response signals. A status change of the space is detected by comparing two of the space features.

An object detection device comprises a transmission sound pressure adjustment unit adjusting a sound pressure of the search wave so that the sound pressure of the search wave or a reflected wave based on the search wave is within a predetermined transmission target range. The transmission unit transmits, as the search wave, a first search wave with a first frequency changing with time at a first rate and a second search wave with a second frequency changing with time at a second rate that is different from the first rate. The transmission sound pressure adjustment unit is configured to adjust the sound pressure of each of the first and second search waves so that the sound pressure of the corresponding one of the first and second search waves or the reflected wave based on the corresponding one of the first and second search waves is within the transmission target range.

Methods, apparatus, systems and articles of manufacture to detect changes in a physical environment are disclosed. An example apparatus includes a descriptor generator to generate a first descriptor, the descriptor generator including: a chirp producer to emit a chirp into the environment, a chirp recorder to record a response to the chirp from the environment, and a chirp response encoder to generate an encoding of the response to the chirp; a descriptor similarity generator to generate a similarity value, the similarity value to compare the first descriptor to a second descriptor; and a physical change indicator to, in response to the similarity value exceeding a similarity threshold, indicate that a physical change has occurred in the environment.

An object detection system includes: a transmission unit configured to sequentially transmit a plurality of transmission waves to which identification information different from one another is applied; a reception unit configured to sequentially receive a plurality of reception waves respectively corresponding to the plurality of transmission waves returned in response to reflection by an object after all the plurality of transmission waves are transmitted by the transmission unit; and a detection processing unit configured to detect information related to the object based on a relationship between the plurality of transmission waves and the plurality of reception waves.

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.

A system configured for vehicle communication includes a first smart apparatus associated with a first vehicle having a first horn and configured to acquire a first target information and a transmission direction information; a first horn control portion embedded in the first vehicle and configured to control the first horn in the first vehicle to send a first sound wave signal modulated by the first target information to a second vehicle based on the transmission direction information; and a second smart apparatus associated with the second vehicle and configured to receive the first sound wave signal and demodulate the first sound wave signal to obtain the first target information.

A sonar device includes a support having negative buoyancy and a linear acoustic reception antenna comprising an elongated body that is elongated from a first end to a second end, the elongated body being connected by the first end at a connection point that is fixed relative to the support, the sonar device being able to be in a reception configuration, wherein the antenna body and the support are fully submerged and wherein the antenna body is able to be in a vertical orientation, wherein it extends substantially vertically from the first end to the second end toward the seabed, the sonar device comprising orientation adjustment means for adjusting, when the sonar device is in the reception configuration and the support is fixed relative to the terrestrial reference frame, an angle of elevation and an azimuth of the second end in the reference frame connected to the support centered on the connection point.