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.

This radar device comprises a signal generation circuit for generating a baseband signal, a code generation circuit for generating a plurality of code sequences, a phase rotation circuit for applying phase rotation based on one of the code sequences from among the plurality of code sequences to the baseband signal and generating a plurality of code multiplexed transmission signals, and a plurality of transmission antennas for transmitting the plurality of transmission signals. The code length of the plurality of code sequences is greater than the code multiplexing number of the plurality of transmission signals.

According to the disclosure, an increase in costs is suppressed and the influence of main bang is reduced. A signal processing device includes a hardware processor programmed to at least: calculate a correction value of strength for each of distances from an antenna based on a received signal including a signal acquired by multiple transmissions and receptions via the antenna; and suppress a level indicated by received data generated based on the received signal for each of the distances by using the correction value for each of the distances.

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for radio frequency (RF) sensing in the millimeter-wave frequency spectrum that can be performed over multiple phases. During a session setup phase, a radar initiator identifies one or more wireless stations (STAs) that are capable of radar ranging and sets up a radar measurement session that includes at least one of the identified STAs. During a measurement negotiation phase, the radar initiator performs a respective beamforming training operation with each STA and indicates, to each STA, one or more parameters associated with the radar measurement session. During a radar measurement phase, the radar initiator transmits radar setup information to, and receives ranging information from, each STA. In some aspects, the radar initiator may perform an object detection operation that indicates a location of an object associated with the ranging information received from each radar STA.

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for radio frequency (RF) sensing in the millimeter-wave frequency spectrum that can be performed over multiple phases. During a session setup phase, a radar initiator identifies one or more wireless stations (STAs) that are capable of radar ranging and sets up a radar measurement session that includes at least one of the identified STAs. During a measurement negotiation phase, the radar initiator performs a respective beamforming training operation with each STA and indicates, to each STA, one or more parameters associated with the radar measurement session. During a radar measurement phase, the radar initiator transmits radar setup information to, and receives ranging information from, each STA. In some aspects, the radar initiator may perform an object detection operation that indicates a location of an object associated with the ranging information received from each radar STA.

A method for forming 3D image data representative of the subsurface of infrastructure located in the vicinity of a moving vehicle. The method includes: rotating a directional antenna, mounted to the moving vehicle, about an antenna rotation axis; performing, using the directional antenna whilst it is rotated about the antenna rotation axis, a plurality of collection cycles in which the directional antenna emits RF energy and receives reflected RF energy; collecting, during each of the plurality of collection cycles performed by the directional antenna.

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.

Provided are systems and methods of using of optical delay lines in RF imagers, e.g., Ultra-wideband (UWB) imagers. In an embodiment, a modulator can be configured to convert radio-frequency signals to optical signal. First and second optical delay lines delay respective first and second optical signals converted by the modulator, and a photodetector can convert the delayed optical signals to at least one electrical signal corresponding to at least one pixel of a radio frequency image. The disclosed systems and methods can also further form a radio-frequency image based on output from the photodetector. In still further embodiments, the photodetector can receive modulated optical signals from an array of optical delays. Also provided are related methods of using the disclosed systems and devices.

A method and apparatus with vehicle radar control is disclosed. An apparatus with vehicle radar control includes a radio frequency (RF) transceiver including a transmitting antenna array and a receiving antenna array, and at least one processor configured to collect environmental information of the vehicle, determine a radar mode of the vehicle based on the collected environmental information, generate one or more control signal configured to control one or more of the transmitting antenna array and the receiving antenna array based on the determined radar mode, and provide the generated one or more control signals to the RF transceiver, wherein one or more of the transmitting antenna array and the receiving antenna array operate according to the one or more generated control signals.

An operation method performed by an apparatus for detecting multiple targets may comprise transmitting first signals using M.sub.t transmit antennas included in the apparatus; receiving the first signals reflected by the multiple targets through M.sub.r receive antennas included in the apparatus; generating a first function for estimating a velocity and an azimuth of each of the multiple targets using the first signals and the reflected first signals; estimating a velocity and an azimuth that maximize a result of the first function as a velocity and an azimuth of a first target closest to the apparatus among the multiple targets; generating a second function by cancelling interference caused by the first target from the first function; and estimating a velocity and an azimuth that maximize a result of the second function as a velocity and an azimuth of a second target among the multiple targets.