According to an example aspect of the present invention, there is provided a method comprising, transmitting by a wireless device, during a first phase, a first probe signal associated with a user and receiving a reflected version of the first probe signal, transmitting by the wireless device, during the first phase, the reflected version of the first probe signal to a ground truth classifier, transmitting by the wireless device, during a second phase, a second probe signal associated with the user and receiving a reflected version of the second probe signal and transmitting by the wireless device, during the second phase, the reflected version of the second probe signal to a trusted apparatus.

A radar detection method may include: transmitting a first radar signal in a field of view and receiving a second radar signal originated from reflections of the first radar signal in the field of view; generating a detection profile by processing the first and second radar signals, the detection profile representing intensities of the second radar signal as a function of positions in the field of view; and analyzing the detection profile to identify targets in the field of view. Analyzing the detection profile may include: using a first mode of analysis, with lower sensitivity, for first cycles, wherein the first mode of analysis is configured to detect a target entering the field of view; using a second mode of analysis, with higher sensitivity, for second cycles following the first cycles, wherein the second mode of analysis is configured to detect stay of the target in the field of view.

Method and system for detecting a cleaning process in a radar level gauge configured to determine a fill level of a product contained in a tank, the radar level gauge comprising a transceiver configured to provide a transmit signal, S.sub.T, to be propagated towards the product by a propagating device, to receive a reflected signal, S.sub.R, resulting from a reflection of the transmit signal at a surface of the product, and to determine a fill level in the tank based on the received reflected signal, wherein the method comprises: at a measurement position above the fill level and a known distance from a reference position near a ceiling of the tank, determining a difference in signal amplitude between at least two different fill level measurements; and if the determined difference in signal amplitude exceeds a predetermined threshold value, determining that a cleaning process is ongoing in the tank.

In a distance detection method, a target apparatus receives a first transmit signal from a detection apparatus. The target apparatus generates a first echo signal by modulating some of reflected signals of the first transmit signal to cause a first Doppler shift between the first echo signal and the first transmit signal. The target apparatus emits the first echo signal to the detection apparatus, which derives its distance from the target apparatus based on the first echo signal.

Provided are a representative point extraction circuitry that extracts a representative reflection point of a target a line segment setting circuitry that sets a plurality of detection line segments of the same length that extend from the representative reflection point and are arranged within the irradiation field at intervals about the representative reflection point as a center, a reflection point counter that counts a coordinate point indicating a reflection level higher than a second threshold value as a reflection point by using the second threshold value, and a reflection point determinator that determines a reflection point counted in the detection line segments to a top second place in which the number of reflection points is large, as a reflection point from the target.

In an embodiment, a method includes: receiving first radar data from a millimeter-wave radar sensor; receiving a set of hyperparameters with a radar processing chain; generating a first radar processing output using the radar processing chain based on the first radar data and the set of hyperparameters; updating the set of hyperparameters based on the first radar processing output using a hyperparameter selection neural network; receiving second radar data from the millimeter-wave radar sensor; and generating a second radar processing output using the radar processing chain based on the second radar data and the updated set of hyperparameters.

The present disclosure is a system comprising at least three electronically steered antennas arranged so that there is a baseline difference of a predetermined amount of wavelength between the centers of the antennas, typically configured as an obtuse or scalene triangle, where the distance between each antenna on an array is selected to provide the required accuracy and precision, the array having a timing circuit to ensure that the beam of each antenna is steered to the same azimuthal and elevation coordinates in space simultaneously. This enables the three electronically steered antennas to operate as an interferometer to determine a bearing to a target to ultimately determine the location thereof. The electronically steered antennas enable the system to be mounted on a platform in a small package that was previously difficult for traditional interferometers.

The concepts, systems and methods described herein are directed towards frequency jump burst-pulse-Doppler (FJB-PD) waveforms and processing to provide wideband, high range resolution (HRR) radar profiling capability in a clutter dense environment. The method includes transmitting a FJB-PD waveform comprising a plurality of frequency steps over a predetermined time period with each frequency step having a plurality of pulses. The method further includes receiving one or more FJB-PD pulse returns corresponding to the FJB-PD waveform and identifying one or more target detections in the one or more FJB-PD pulse returns. A set of range swaths may be extracted for each of the one or more target detections and a wideband spectrum may be generated for each of the sets of range swaths using FJB coherent integration. A clutter suppressed HRR profile may be generated for each of the target detections based on the respective wideband spectrum.

Remote recovery of acoustic signals from passive sources is provided. Wideband radars, such as ultra-wideband (UWB) radars can detect minute surface displacements for vibrometry applications. Embodiments described herein remotely sense sound and recover acoustic signals from vibrating sources using radars. Early research in this domain only demonstrated single sound source recovery using narrowband millimeter wave radars in direct line-of-sight scenarios. Instead, by using wideband radars (e.g., X band UWB radars), multiple sources separated in ranges are observed and their signals isolated and recovered. Additionally, the see-through ability of microwave signals is leveraged to extend this technology to surveillance of targets obstructed by barriers. Blind surveillance is achieved by reconstructing audio from a passive object which is merely in proximity of the sound source using clever radar and audio processing techniques.

A polarimetric radar system for object classification and road condition estimation includes a radar transmitter unit for transmitting radar waves of different polarizations, a radar receiving unit for receiving radar waves of different polarizations, a radar signal generating unit for generating and providing the radar waves to be transmitted, a signal processing circuitry for processing the generated and received radar waves, and a signal evaluation unit. The signal evaluation unit receives processed signals from the signal processing circuitry, estimates values for a set of predetermined object parameters on the basis of the received processed signals, and selects an object class from a plurality of predetermined object classes upon detecting a match of the estimated values with one out of a plurality of predetermined sets of object parameters. The signal evaluation unit is configured to provide information that is indicative of the at least one classified object.