An ultrasonic detecting device may include a transmitter, a receiver, a motor, and processing circuitry. The transmitter may transmit a sequence including a first pulse wave and a second pulse wave separated by a time interval shorter than a time required for an ultrasonic wave to make a round trip underwater to a detection range. The receiver may convert reflection waves of the first and second pulse waves into echo signals. The motor may rotate the receiver. The processing circuitry may acquire, from the echo signals, a first echo signal and a second echo signal, generate first image data based on the first echo signals and second image data based on the second echo signals, and generate synthesized image data based on an angular position of the receiver when the first image data is generated, and an angular position of the receiver when the second image data is generated.

A wideband sonar receiver is provided that includes: a selectable bandpass filter adapted to filter a received sonar signal to produce a filtered signal and a correlator adapted to correlate the baseband samples with baseband replica samples to provide a correlated signal. In addition, the wideband sonar receiver may include a shaping filter to shape unshaped received pulses. Finally, a variety of sonar processing algorithms are described with regard to reducing clutter and interference, target detection, and bottom detection.

An ultrasound ranging device is provided. The ultrasound ranging device includes an ultrasound transmitter, an ultrasound receiver, a random number generator and a processor. The ultrasound transmitter transmits an ultrasonic signal. The ultrasound receiver receives a reflected signal which is generated when the ultrasonic signal meets an obstacle. The random number generator generates a random number. The processor is coupled to the random number generator to obtain the random number and according to the random number, the processor determines the delay time for the ultrasound transmitter transmitting the ultrasonic signal. After the delay time, the ultrasound transmitter transmits the ultrasonic signal to perform ultrasound ranging.

A method for measuring a distance to a target in a multi-user environment by means of at least one sensor, comprising: irradiating the environment by means of a series of radiation pulses, wherein series of radiation pulses are emitted at a determined repetition rate and with a determined random delay; collecting pulses that are reflected or scattered from the environment to at least a detector connected to at least one chronometer; assigning a timestamp at every detected pulse on the detector; subtracting the added delay from every registered timestamp coming from the chronometer, the result corresponding to the time of arrival; determining the statistical distribution of said time of arrival; determining the distance to the target from said statistical distribution.

An embodiment provides a method for measuring velocity and depth of fluid flow in a channel, including: transmitting, using a transmitter, directed energy comprising a single energy beam slant-wise toward a surface of a fluid in a fluid channel producing a plurality of reflections, wherein the transmitting comprises modulating a frequency associated with the single energy beam; detecting, at a receiver, received signals from the plurality of reflections; and determining, based upon differences between parameters of the transmitted single energy beam and parameters of the received signals, the velocity of the fluid and the depth of the fluid. Other embodiments are described and claimed.

In an emission process for remote sensing, pulse signals (630) are periodically produced in elementary time windows spaced one pulse period (T) apart, and waves corresponding to those signals are emitted towards remote objects, so as to enable to monitor waves transmitted by those objects upon receiving the emitted waves. The emission of those waves is periodically prevented, according to at least one inhibition period (3T, 5T) proportional to the pulse period and equal to at least three times that pulse period. Parameters are set, suited to producing measurement information on the objects from the wave monitoring, based on at least part of a frequency content of the transmitted waves to which the pulse and inhibition periods contribute. Applications to lidars, radars, active sonars and ultrasound monitoring.

An echo measurement system transmits a transmitted-signal which is modulated over a period of time corresponding to a modulation duration. The modulation could be, for example, modulation to represent a coded signal. A transducer (2), which may be common between transmission and reception, receives a received-signal which is cross-correlated with the transmitted-signal. The transmitted-signal comprises a plurality of transmission periods separated by a plurality of transmission pauses. The modulation duration extends over two or more of the transmission periods and the duration of the transmission pauses is varied within a range of transmission pause duration. The technique seeks to improve the signal-to-noise ratio without imposing undesirable other constraints.

The invention relates to a method for operating at least one ultrasonic sensor (4, 6) of a driver assistance system (2) in a motor vehicle (1), wherein an output sound signal (S.sub.A) of the ultrasonic sensor (4, 6) is modulated in accordance with a type of modulation and by means of this modulation, a specific codeword is impressed on the output sound signal (S.sub.A). For at least two mutually different functionalities (8 to 12) of the driver assistance system (2), different types of modulation are in each case used for the modulation of the output sound signal (S.sub.A) and/or in each case different lengths of the codeword.

A wideband sonar receiver is provided that includes: a selectable bandpass filter adapted to filter a received sonar signal to produce a filtered signal and a correlator adapted to correlate the baseband samples with baseband replica samples to provide a correlated signal. In addition, the wideband sonar receiver may include a shaping filter to shape unshaped received pulses. Finally, a variety of sonar processing algorithms are described with regard to reducing clutter and interference, target detection, and bottom detection.