Beamformed sonar data is compressed before communicating the data to a storage step or to a further processing step. At lease some of the beams of the compressed beamformed data have values for at least two different ranges.

A method for measuring, using a radar or sonar, the velocity with respect to the ground of a carrier moving parallel to the ground, includes the following steps: a) orienting the line of sight of the radar or sonar toward the ground; b) emitting a plurality of radar or sonar signals (P.sub.1-P.sub.N) that are directed toward the ground, and acquiring respective echo signals (E.sub.1-E.sub.N); c) processing the acquired echo signals so as to obtain, for one or more echo delay values, a corresponding Doppler spectrum; d) for the or at least one the echo delay value, determining a high cut-off frequency of the corresponding Doppler spectrum; and e) computing the velocity of the carrier with respect to the ground on the basis of the one or more high cut-off frequencies. A system allowing such a method to be implemented.

Composite burst signaling to provide robust multi-channel sensor array performance in systems for parking assistance, blind spot monitoring, and driver assistance. An illustrative method embodiment includes driving an acoustic transducer to send composite acoustic bursts. Each composite acoustic burst includes multiple individual bursts associated with respective frequency bands, the frequency band arrangement providing a source-specific burst signature. The method further includes receiving self-generated echo signals responsive to the composite acoustic bursts from the transducer and potentially including extra echoes responsive to acoustic bursts from other sources; categorizing received echo signals by source based on the burst signature; and using the self-generated echoes exclusive of the extra echoes to determine a distance or time of flight from the transducer.

Embodiments of the present disclosure describe an efficient O(n log n) method that implements the Inverse Chirp Z-Transform (ICZT). This transform is the inverse of the well-known forward Chirp Z-Transform (CZT), which generalizes the fast Fourier transform (FFT) by allowing the sampling points to fall on a logarithmic spiral contour instead of the unit circle. Thus, the ICZT can be viewed as a generalization of the inverse fast Fourier transform (IFFT).

A distance detection apparatus includes a wave transmitter configured to transmit a transmission wave, a wave receiver configured to receive the transmission wave which is reflected by an object, a storage portion configured to store a transmission signal, a correlation processing portion configured to obtain a correlation value between the transmission signal and a reception signal corresponding to a reception wave, and a detection portion configured to detect a distance to the obstacle in a case where the correlation value indicates that the transmission signal and the reception signal are similar to each other at a level which is equal to or greater than a predetermined level.

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.

The invention relates to a method for identifying parking spaces, including emitting an ultrasonic signal and receiving a reflected signal; and providing a grid which of a region having a plurality of cells. Each cell is assigned to a partial region of the region surrounding the vehicle and an occupancy value is assigned to each cell. The reflected signal is assigned to a set of cells of the grid based on a transit time of the ultrasonic signal between emission and reception. The occupancy values of the cells to which the reflected signal is allocated are increased by a specific value. An occupancy information item is determined based on the occupancy values of the cells. The signal emitting/receiving and the reflected signal assigning are repeated multiple times. Parking space identification is performed based on an occupancy status of the cells specified using the occupancy information item determination.

A burst drive signal has a sensor drive period for transmitting a first drive signal, and an interval period provided between the sensor drive periods adjacent to each other, for transmitting a second drive signal. The first drive signal has a frequency within a frequency band of a band pass filter. The second drive signal has a frequency that is different from a resonant frequency of a sensor element and is outside the frequency band of the band pass filter.

An apparatus for correcting an input signal is configured for receiving the input signal, the received input signal comprising a series of input values. The apparatus is configured for matching a series of template values to the series of input values by warping the series of template values and the series of input values relatively to each other so as to assign one or more template values to one or more input values, wherein the series of template values represents an approximation of a noise signal that is expected to be comprised in the input signal. The apparatus is configured for obtaining a series of corrected input values based on a mismatch between the input values and their respective assigned template values. The apparatus is configured for providing a corrected signal based on the series of corrected input values.

A method for providing an estimate of a time-of-flight between an ultrasonic signal emitted by a device and an ultrasonic echo signal returned by a target object hit by the ultrasonic signal and received at the device. The method includes acquiring the ultrasonic echo signal thereby obtaining an electric echo signal; determining a noise power of the electric echo signal; determining an envelope signal indicative of an envelope of the electric echo signal; determining a portion of the envelope signal based on at least one operative parameter, the at least one operative parameter being determined according to Particle Swarm Optimization; processing the portion of the envelope signal and the noise power of the echo ultrasonic signal according to an Unscented Kalman Filter to obtain an estimate of the envelope signal, wherein the estimate of the envelope signal is a regenerated version of the envelope signal being regenerated from the portion of the envelope signal, the processing being based on at least one Unscented Kalman Filter parameter determined according to the Particle Swarm Optimization, and providing the estimate of the time-of-flight according to the estimate of the envelope signal.