Techniques are discussed for determining reflected returns in radar sensor data. In some instances, pairs of radar returns may be compared to one another. For example, a velocity associated with a first radar return may be projected onto a radial direction associated with a second radar return to determine a projected velocity. In some examples, the second radar return may be a reflected return if the magnitude of the projected velocity corresponds to a magnitude of the second radar return. In some instances, a vehicle, such as an autonomous vehicle, may be controlled at the exclusion of information from reflected returns.

Systems, methods, and devices relating to radar and radar-based applications. A number of comparators are coupled in parallel with each comparator comparing an incoming signal and a predetermined value. If the predetermined value is exceeded by the incoming signal, the comparator output is set to trigger a flip flop. The predetermined value changes with each comparator and, with the signal being the radar reflection from a radar pulse, this allows for the detection of the peak value of the incoming signal. The circuit may be extended so that the output of the comparator which is triggered by the highest peak from the incoming signal is latched. Other variants include being able to count the clock cycles before the highest peak is detected within the range cell.

The radar system 11 comprises a plurality of transmission antennas 12 which irradiate electromagnetic waves, a plurality of receiving antennas 13 which receive the irradiated electromagnetic waves that have been reflected and generating measurement signals, radar signal transmission and receiving means 14 for obtaining the measurement signals, movement estimation means 15 for estimating the movement of an object, and motion-compensated image generation means 16 for generating a radar image based on the measurement signals and the estimated object movement.

A method and sensor system are disclosed for automatically determining object sensor position and alignment on a host vehicle. A radar sensor detects objects surrounding the host vehicle in normal operation. Static objects are identified as those objects with ground speed approximately equal to zero. Vehicle dynamics sensors provide vehicle longitudinal and lateral velocity and yaw rate data. Measurement data for the static objects—including azimuth angle, range and range rate relative to the sensor—along with the vehicle dynamics data, are used in a recursive geometric calculation which converges on actual values of the radar sensor's two-dimensional position and azimuth alignment angle on the host vehicle.

An object tracking apparatus acquires detection information from a sensor mounted to a moving body, detects an object, and calculates a distance, a relative velocity, and an orientation thereof. For the initially detected object, the apparatus calculates aliased velocities of which aliasing from the relative velocity is assumed, and generates target candidates corresponding to the aliased velocities. For each target candidate, the apparatus estimates a current state of the target candidate from a past state thereof and observation information, and selects the target candidate estimated to be a true target from the target candidates for the same object. The apparatus calculates, as a reference velocity, an aliased velocity of the relative velocity that is equal to or greater than a velocity lower-limit value and is most negative or smallest in magnitude. The apparatus calculates the aliased velocities being the reference velocity aliased 0 to n times in a positive direction.

The disclosure provides a radar apparatus. The radar apparatus includes a transmitter that transmits a first chirp. The first chirp is scattered by one or more obstacles to generate a first plurality of scattered signals. A plurality of receivers receives the first plurality of scattered signals. Each receiver of the plurality of receivers generates a digital signal in response to a scattered signal of the first plurality of scattered signals. A processor is coupled to the plurality of receivers and receives the digital signals from the plurality of receivers. The processor performs range FFT (fast fourier transform) and angle FFT on the digital signals received from the plurality of receivers to generate a first matrix of complex samples.

A vehicle radar sensor unit (2) arranged to acquire a plurality of radar detections, and including an antenna arrangement (3), a transmitter unit (4), a receiver unit (5) and a processing unit (6). The antenna arrangement (3) has at least two transmitter antennas (7, 8) and at least two receiver antennas (9, 10, 11, 12), where two transmitter antennas (7, 8) have a vertical spacing (h) between their respective phase centers (17, 18) that exceeds half the free-space wavelength of the transmitted signal. The processing unit (5) is arranged to determine a first radial velocity of each radar detection by tracking the change of radial distance (r) to each radar detection for a plurality of radar cycles; determine a second radial velocity that best matches the first radial velocity; track a plurality of measured heights (z) as a function of radial distance (r); and to choose a measured height (z.sub.GT) among the tracked measured heights (z) that has a minimal change from radar cycle to radar cycle.

A method for determining a movement vector of a motor vehicle includes: determining, via a radar system of the vehicle, at two successive instants, positions, relative to the vehicle, of elements of an environment of the vehicle that are static relative to the environment, associating the positions determined at these two successive instants with each other in such a way as to form different pairs of positions each grouping together the preceding position and the subsequent position of a given element of the environment, and determining the movement vector of the vehicle by linear regression, based on the pairs of positions thus formed.

Radar systems are disclosed having phase measures limited to +/−π. An optical flow method considers the time derivative of the range with respect to phase (or velocity), and gives an indication of whether the phase is outside the measurable range by comparing the derivatives to forward and reverse wrap thresholds.

A method for determining an ego-velocity estimated value and an angle estimated value of targets using a synthetic aperture radar sensor. A distance is measured between the synthetic aperture radar sensor and each respective target. A relative velocity of the respective target is measured using the Doppler effect. An angle estimation of an angle estimated value takes place, which characterizes the angle between the direction of the ego-velocity of the synthetic aperture radar and the respective target. An individual ego-velocity estimated value of the synthetic aperture radar sensor is ascertained using the relative velocity and the angle estimated value for each target. A classification and distribution of the individual ego-velocity estimated values relating to stationary targets takes place, whose individual ego-velocity estimated values are situated within a predefinable range relative to one another, and relating to moving targets, whose individual ego-velocity estimated values are situated outside the range.