Method for unambiguously determining a range and/or a relative speed of an object, driver assistance device and motor vehicle

摘要

A method for unambiguous determination of a range to and/or of a relative velocity of an object with respect to a motor vehicle is disclosed. An unambiguity area (RUn) for the range and/or an unambiguity area (VUn) for the relative velocity may be determined by means of a frequency-modulation continuous-wave radar in the motor vehicle, with a predetermined sequence of frequency-modulated signal pulses being transmitted by the frequency-modulation continuous-wave radar in a measurement cycle. Mutually different unambiguity areas (RUn) for the range and/or mutually different unambiguity areas (VUn) for the relative velocity are defined for at least two successive measurement cycles, and the range and/or the relative velocity are/is determined on the basis of, in each case, at least one measured value for the range and/or for the relative velocity from each measurement cycle.

主权项

1. A method for unambiguous determination of a range to and of a relative velocity of an object with respect to a motor vehicle using a frequency-modulation continuous-wave radar in the motor vehicle, the method comprising:
transmitting predetermined sequences of frequency-modulated signal pulses by the frequency-modulation continuous-wave radar in a measurement cycle; determining an unambiguity area (RUn) for the range and an unambiguity area (VUn) for the relative velocity, based on the predetermined sequences; defining mutually different unambiguity areas (RUn) for the range and mutually different unambiguity areas (VUn) for the relative velocity for at least two successive measurement cycles; determining the range and the relative velocity on the basis of, in each case, at least one measured value for the range or for the relative velocity from each of the at least two successive measurement cycles; defining a tolerance band around every measured value for the range from a first measurement cycle of the at least two successive measurement cycles; determining whether the measured value for the range from a successive measurement cycle of the at least two successive measurement cycles is within the tolerance band; indicating an object located at the measured value for the range from the successive measurement cycle of the at least two successive measurement cycles if the measured value for the range from the successive measurement cycle of the at least two successive measurement cycles is determined to be within the tolerance band; and filtering out the measured value for the range from the successive measurement cycle of the at least two successive measurement cycles if the measured value for the range from the successive measurement cycle of the at least two successive measurement cycles is determined to be outside of the tolerance band, wherein the definition of different unambiguity areas (RUn) for the range comprises mutually different frequency shifts (fShift) being set for respective sequences of frequency-modulated signal pulses, wherein the definition of different unambiguity areas (VUn) for the relative velocity comprises mutually different pulse repetition frequencies (PRF) being set for the respective sequences of frequency-modulated signal pulses, wherein mutually different pulse repetition frequencies (PRF) are set by variation of a time duration (TPause) of a pause between each frequency-modulated signal pulse of each of the predetermined sequences, and wherein the mutually different frequency shifts (fShift) and the mutually different pulse repetition frequencies (PRF) are selected during operation of the frequency-modulation continuous-wave radar.