An RFID detector suitable for use in a passive RFID tag system that employs frequency hopping spread spectrum (FHSS) operation obtains an indication of at least one characteristic of a CW RF signal employing a hopped-to carrier frequency that is being transmitted from an RFID tag reader, e.g., for use in activating the RFID tag to be located, the indication of the characteristic being obtained based on a signal that is received from a source other than the RFID detector. The RFID detector may use the obtained indication of the characteristic of the CW RF signal to determine at least one position related parameter for the RFID tag. A location, e.g., of the tag, of a group of tags, of the RFID detector, or of another RFID detector, may be determined based on the position parameter.

A sensor device for measuring a motion of a vehicle includes a light source for radiating light on a region on a ground below the vehicle in temporal intervals and to produce a spot of increased temperature; a heat detection unit, which is mountable at an underside of the vehicle for detecting a position of the spot on the ground at the temporal intervals; and a control unit for receiving data about a measured time of the spot and the position of the spot from the heat detection unit and to estimate a change of the position of the spot in vehicle coordinates.

A collision determining unit (404) determines whether a vehicle (1000) collides with an object (1001) when a Doppler velocity component between the vehicle (1000) and the object (1001) varies to a first reference value, or when the vehicle (1000) has traveled to a range R corresponding to the first reference value.

A collision determining unit (404) determines whether a vehicle (1000) collides with an object (1001) when a Doppler velocity component between the vehicle (1000) and the object (1001) varies to a first reference value, or when the vehicle (1000) has traveled to a range R corresponding to the first reference value.

A computer includes a processor and a memory storing instructions executable by the processor to receive radar data from a radar sensor of a vehicle; demarcate a zone of coverage of the radar sensor, the zone of coverage having an area based on a number of objects indicated by the radar data; and after demarcating the zone of coverage, in response to detecting a newly present object in the zone of coverage, adjust a scanning rate of the radar sensor based on a distance of the newly present object from the radar sensor.

A computer includes a processor and a memory storing instructions executable by the processor to receive radar data from a radar sensor of a vehicle; demarcate a zone of coverage of the radar sensor, the zone of coverage having an area based on a number of objects indicated by the radar data; and after demarcating the zone of coverage, in response to detecting a newly present object in the zone of coverage, adjust a scanning rate of the radar sensor based on a distance of the newly present object from the radar sensor.

A system comprises a set of sensors on a first end of a vehicle having the first end and a second end, and a controller. The sensors are configured to generate corresponding sensor data based on a detected object along a direction of movement of the vehicle. The controller is configured to compare a time at which the first sensor detected the object with a time at which the second sensor detected the object to identify the first end or the second end as a leading end of the vehicle, and to calculate a position of the leading end of the vehicle based on the sensor data generated by one or more of the first sensor or the second sensor. The controller is also configured to generate a map of the plurality of objects based on the sensor data.

A system comprises a set of sensors on a first end of a vehicle having the first end and a second end, and a controller. The sensors are configured to generate corresponding sensor data based on a detected object along a direction of movement of the vehicle. The controller is configured to compare a time at which the first sensor detected the object with a time at which the second sensor detected the object to identify the first end or the second end as a leading end of the vehicle, and to calculate a position of the leading end of the vehicle based on the sensor data generated by one or more of the first sensor or the second sensor. The controller is also configured to generate a map of the plurality of objects based on the sensor data.

A radar system configured to determine radar-ground distance measurements. The radar system includes transmission and reception means configured to transmit two radiofrequency signals towards the ground and to receive the signals obtained by the reflection of the two transmitted signals by the ground and computation means configured to determine the frequential representations of the transmitted signals and of the received signals and determine a frequential quantity as a function of the frequential representations. The radar system is wherein the computation means are configured to sample the frequential quantity over a determined number of samples, which provides a sampled signal; determine a number of frequency measurements as a function of a constant distance measurement accuracy value; determine frequency measurements by applying to the sampled signal a spectral decomposition by fast Fourier transform using a decimation of the sampled signal in a ratio dependent on the distance measurement accuracy value, and determine a distance measurement corresponding to each frequency measurement.

Disclosed is a method and a system for retrieving a location of a base point of a wheeled vehicle in a local coordinate system of a tridimensional sensor mounted on the vehicle. The method includes acquiring point cloud frames while the wheeled vehicle is moving along a straight path and a curved path and a point cloud representative of a portion of the vehicle, computing a main direction vector, a main direction line and a location of an instantaneous centre of rotation of the wheeled vehicle in the local coordinate system, and retrieving the location of the base point.