US 12,461,199 B2
Axial misalignment estimation apparatus
Katsuhiko Kondo, Nisshin (JP); and Takuya Takayama, Kariya (JP)
Assigned to DENSO CORPORATION, Kariya (JP)
Filed by DENSO CORPORATION, Kariya (JP)
Filed on Feb. 2, 2023, as Appl. No. 18/163,778.
Application 18/163,778 is a continuation of application No. PCT/JP2021/028613, filed on Aug. 2, 2021.
Claims priority of application No. 2020-133860 (JP), filed on Aug. 6, 2020.
Prior Publication US 2023/0176186 A1, Jun. 8, 2023
Int. Cl. G01S 13/72 (2006.01); G01S 7/40 (2006.01); G01S 13/931 (2020.01)
CPC G01S 7/4021 (2013.01) [G01S 13/72 (2013.01); G01S 13/931 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An axial misalignment estimation apparatus that estimates an axial misalignment angle of a radar apparatus that is mounted to a moving body, the axial misalignment estimation apparatus comprising:
a reflection point information acquiring unit that is configured to acquire, for each reflection point detected by the radar apparatus, a relative speed of the reflection point relative to the radar apparatus and an orientation angle of the reflection point with reference to a direction that is prescribed based on design as a reference of the radar apparatus, at every measurement cycle set in advance;
a moving body speed acquiring unit that is configured to acquire a moving body speed that is a speed of the moving body, at every measurement cycle;
an extracting unit that is configured to extract, as a stationary reflection point, a reflection point that is assumed to be a point of reflection by a stationary object based on a predetermined extraction condition, among the reflection points detected by the radar apparatus;
an aliasing processing unit that is configured to determine whether aliasing is present at the orientation angle of the stationary reflection point and correct the orientation angle of the stationary reflection point in which aliasing is determined to be present; and
an axial misalignment estimating unit that is configured to estimate the axial misalignment angle based on the orientation angle of the stationary reflection point, wherein:
the extraction condition is prescribed based on a relational expression that is established between an observed speed ratio that is a ratio of the relative speed of the reflection point and the moving body speed, and an estimated speed ratio that is the observed speed ratio estimated based on the orientation angle of the reflection point in a case where the reflection point is a point of reflection by a stationary object;
the aliasing processing unit is configured to determine, for each stationary reflection point, whether aliasing is present at the orientation angle of the stationary reflection point based on a first estimated speed ratio that is the estimated speed ratio calculated using the orientation angle that is corrected based on the axial misalignment angle estimated at the measurement cycles up to a previous measurement cycle, and at least one second estimated speed ratio that is the first estimated speed ratio presuming that aliasing is present at the orientation angle; and
the axial misalignment estimating unit is configured to estimate the axial misalignment angle based on the corrected orientation angle for the stationary reflection point of which the orientation angle is corrected by the aliasing processing unit.