An aspect of the present disclosure is directed to and provides radar-reflecting systems and apparatus that employ metasurfaces to produce enhanced radar cross sections that are greater than those produced by the geometry of the surfaces alone. Another aspect of the present disclosure is directed to and provides heat-ducting systems and apparatus that include metasurfaces. A further aspect of the present disclosure is directed to and provides cards with metasurfaces. Exemplary embodiments utilize fractal plasmonic surfaces for a metasurface.

The invention relates to a radar reflector (1) for reflecting radar radiation (2), comprising at least one reflection element (5) rotatable about a central axis (4) of the radar reflector (1) and an adjusting device (7) for changing and/or parameterizing a characteristic of a radar echo (3) of the radar reflector (1). At least one of the following parameters can be changed by means of the adjusting device (7): the angular velocity ω of rotational motion of the at least one reflection element (5) about the central axis (4); an effective reflection area of the at least one reflection element (5); and a fastening position p of the at least one reflection element (5) relative to the central axis (4). The invention also relates to a system for controlling automated operation of a motor vehicle, comprising at least one radar reflector of this type, and to a motor vehicle (23), which has a radar sensor (24) and is designed to automatedly carry out a predefined sequence of driving maneuvers in accordance with a sensed characteristic of the radar echo of the radar reflector.

Disclosed are techniques for non-line-of-sight (NLOS) target detection. In an aspect, a source vehicle receives, from a roadside unit (RSU), a notification that the RSU is capable of repeating radar signals transmitted by the source vehicle in NLOS directions from the source vehicle, receives, from an active radar repeater associated with the RSU, radar signals for a radar beam sweep in at least one NLOS direction from the source vehicle, receives an angle of each beam of the radar beam sweep, and performs target object detection based on the radar signals for the at least one NLOS direction and the angle of each beam of the radar beam sweep. Example architectures for the active radar repeater are also disclosed.

An aspect of the present disclosure is directed to and provides radar-reflecting systems and apparatus that employ metasurfaces to produce enhanced radar cross sections that are greater than those produced by the geometry of the surfaces alone. Another aspect of the present disclosure is directed to and provides heat-ducting systems and apparatus that include metasurfaces. A further aspect of the present disclosure is directed to and provides cards with metasurfaces. Exemplary embodiments utilize fractal plasmonic surfaces for a metasurface.

A method of using a directional sensor for the purposes of detecting the presence of a vehicle or an object within a zone of interest on a roadway or in a parking space. The method comprises the following steps: transmitting a microwave transmit pulse of less than 5 feet; radiating the transmitted pulse by a directional antenna system; receiving received pulses by an adjustable receive window; integrating or combining signals from multiple received pulses; amplifying and filtering the integrated receive signal; digitizing the combined signal; comparing the digitized signal to at least one preset or dynamically computed threshold values to determine the presence or absence of an object in the field of view of the sensor; and providing at least one pulse generator with rise and fall times of less than 3 ns each and capable of generating pulses less than 10 ns in duration.

A reflector having an information generation function, wherein information allowing a quick and clear understanding of a traffic system and the surrounding environment thereof can be generated by a combination of unit reflectors recognizable by a light detection and ranging (Lidar) or radio detecting and ranging (Radar) system, is proposed. The reflector includes a plurality of unit reflectors for representing information through code generation, wherein each of the unit reflectors represents information by reflecting light beams or radio waves therefrom or transmitting the same therethrough, whereby binary-coded information is generated using the reflector, which allows a Lidar system or a Radar system to recognize the generated information.

A radar-optical fusion article for attachment to a substrate is described. The radar-optical fusion article includes a first retroreflective layer which is configured to retroreflect at least a portion of light having a wavelength in a range from about 400 nm to about 2500 nm. The radar-optical fusion article includes a second retroreflective layer disposed adjacent to the first retroreflective layer. The second retroreflective layer is configured to retroreflect at least a portion of an electromagnetic wave having a frequency in the range from about 0.5 GHz to about 100 GHz.

A mobile robot is configured for operation in a commercial or industrial setting, such as an office building or retail store. The robot can patrol one or more routes within a building, and can detect violations of security policies by objects, building infrastructure and security systems, or individuals. In response to the detected violations, the robot can perform one or more security operations. The robot can include a removable fabric panel, enabling sensors within the robot body to capture signals that propagate through the fabric. In addition, the robot can scan RFID tags of objects within an area, for instance coupled to store inventory. Likewise, the robot can generate or update one or more semantic maps for use by the robot in navigating an area and for measuring compliance with security policies.

A tag enhances vehicle radar visibility of objects by increasing the effective radar cross-section of the object, allowing detection at longer ranges and providing the vehicle/driver with more time to avoid a collision. The tag may include a receive antenna and a bandpass filter configured to receive a signal from the receive antenna and to allow a portion of the frequency range of the signal from the receive antenna through. The tag may also include an amplifier configured to receive and amplify the signal with the portion of the frequency range from the bandpass filter. The tag may further include a transmit antenna configured to transmit the amplified signal. The receive antenna, the transmit antenna, and the amplifier may be configured such that antenna-to-antenna isolation between the receive antenna and the transmit antenna is greater than a gain of the amplifier.

Methods, systems, and devices for wireless communications are described. A vehicle-based wireless device may receive a calibration availability message from a roadside unit identifying one or more calibration characteristics of a calibration object associated with the roadside unit. The vehicle-based wireless device may determine one or more sensor characteristics for a sensor of the vehicle and the vehicle. The vehicle-based wireless device may measure the one or more calibration characteristics of the calibration object using the sensor while the vehicle is within a defined range of the calibration object. The vehicle-based wireless device may perform a calibration procedure to calibrate the sensor based at least in part on the identified one or more calibration characteristics, the measured one or more calibration characteristics, and the one or more sensor characteristics.