A method and apparatus for processing a transceiver signal (115) detected by a transceiver (110). The method includes obtaining (51) a processed signal from the transceiver signal (115), the processed signal having frames (200, 300) corresponding to respective time intervals (t1, t2, t3, t4), wherein the frames define bins (210, 310) configured according to a quantized resolution (dr) of the transceiver signal (115). The method further includes obtaining (S2) data related to a relative motion of the transceiver (110) during a time interval (t1, t2, t3, t4) and initializing (S3) a residual distance to zero. For each frame (200, 300) and each respective time interval (t1, t2, t3, t4) the method further includes determining (S4) a shift distance (ds1, ds3) corresponding to a sum of the residual distance and a distance value (d1, d2) corresponding to a relative motion of the transceiver (110) in the respective time interval (t1, t2, t3, t4) and rounding (S5) the determined shift distance (ds1, ds3) with respect to the distance resolution (dr) to a rounded shift distance. The method then further includes updating (S6) the residual distance based on a difference between the determined shift distance (ds1, ds3) and the rounded shift distance, and generating (S7) an adjusted frame (304) by shifting the bins (310) of the frame by the rounded shift distance to account for relative transceiver motion with respect to the object (150) in the respective time interval. The method finally includes processing (S8) the signal by integrating bin values (210, 310) over the adjusted frames (300).

Various sensors, sensor controllers, and sensor control methods are provided with model-based sideband balancing. In one illustrative embodiment, a controller for a piezoelectric transducer includes a transmitter, a receiver, and a processing circuit coupled to the transmitter and receiver. The processing circuit performs calibration and echo detection, the calibration including: sensing the piezoelectric transducer's phase response as a function of frequency; deriving equivalent circuit parameters for the piezoelectric transducer from the phase response; and determining a sideband imbalance based on one or more of the equivalent circuit parameters. Once the sideband imbalance is identified, the processing circuit may perform echo-detection processing that accounts for the sideband imbalance.

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.

Methods and apparatus are described for implementing a coding scheme on ultrasound signals received by a plurality of ultrasonic transducers. The coding, and subsequent decoding, may allow for multiple ultrasonic transducers to be operated in a receive mode simultaneously while still differentiating the contribution of the individual ultrasonic transducers. Improved signal characteristics may result, including improved signal-to-noise ratio (SNR).

An object detection device includes: a transmission unit transmitting a first transmission wave; a reception unit receiving a first reception wave reflected by an object; a signal processing unit sampling a first processing target signal according to the first reception wave and acquiring a difference signal based on a difference between the first processing target signal for at least one sample at a certain detection timing, and the first processing target signal for a plurality of samples in at least one of first and second periods; a threshold setting unit setting a threshold as a comparison target with the value of the difference signal, based on variation in the values of the first processing target signal for the plurality of samples; and a detection unit detecting information about the object at the detection timing based on a comparison result between the value of the difference signal and the threshold.

The invention relates to a method for operating ultrasonic sensors) for a motor vehicle, including emitting a plurality of ultrasonic signals by respective ultrasonic sensors. The ultrasonic signals include a sequence of elementary signals. The elementary signals have signal pauses and a plurality of different signal pulses. The ultrasonic signals differ from one another by the sequence of the elementary signals. The method further includes receiving reflected ultrasonic signals, wherein the received ultrasonic signals are associated with the emitted ultrasonic signals on the basis of the sequences of the elementary signals.

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 object detection device includes: a transmission unit transmitting a first transmission wave; a reception unit receiving a first reception wave reflected by an object; a signal processing unit sampling a first processing target signal according to the first reception wave and acquiring a difference signal based on a difference between the first processing target signal for at least one sample at a certain detection timing, and the first processing target signal for a plurality of samples in at least one of first and second periods; a threshold setting unit setting a threshold as a comparison target with the value of the difference signal, based on variation in the values of the first processing target signal for the plurality of samples; and a detection unit detecting information about the object at the detection timing based on a comparison result between the value of the difference signal and the threshold.

A system produces sensed images. The system includes a sensor array, an image display device, and a processor that generates an image illustrating contents of an expanded field of view. The processor receives sensor element data from the sensor array, performs zero padding and discrete Fourier transform to result in a sensor wavenumber data buffer. The processor determines reference point locations, and generates a reference Fresnel field. The processor obtains an inverse Huygens-Fresnel transfer data buffer based on the reference Fresnel field. The processor multiplies each data element of the sensor wavenumber buffer with each corresponding data element of the inverse Huygens-Fresnel transfer data buffer. The processor generates a rectilinear spectrum data buffer based on the multiplication. The processor performs Stolt mapping and uniformly resampling to achieve image data.

This disclosure describes presence-detection devices that detect movement of a person by emitting ultrasonic signals into an 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. The techniques include downsampling the audio signals from the carrier frequency range down to a frequency range with a center frequency around 0 Hz. A filter is applied to attenuate signals around 0 Hz and below (or above), such as the emitted signals. In addition to removing the emitted signals, the negative side (or positive side) of the audio signals are removed, but the Doppler shift is still represented in the remaining portion of the audio signals. By removing a portion of the audio signals, the amount of processing required to detect the Doppler shift in the reflections of the ultrasonic signals is reduced.