Imaging radar sensor with horizontal digital beam forming and vertical object measurement by phase comparison in mutually offset transmitters

A device for determining a position of an object in a three-dimensional space, the device comprising:

• at least two switchable transmitting antennas each arranged in a corresponding line in a vertical direction, the at least two switchable transmitting antennas having different vertical positions of their respective phase centers;
• a plurality of receiving antennas spaced apart from one another in the horizontal direction, the transmitting antennas being spaced apart a distance in the horizontal direction that corresponds to a horizontal distance between two adjacent receiving antennas;
• and
• a display device,
• wherein the device is a radar sensor configured to determine the position of the object, wherein determining the position of the object comprises:
• receiving a sequence of signals sent in chronological succession by the transmitting antennas and reflected from the object;
• digitizing the received signals, and
• interlinking the digitized signals to form a number of bundled antenna beams by a digital beam-forming method, and
• determining a vertical position of the object based on a relationship:
• ϕ
• =
• a
• ⁢
• ⁢
• sin
• (
• β
• ⁢
• m
• -
• α
• 2
• ⁢
• π
• ⁢
• z
• λ
• )
• ,
• wherein ϕ is the vertical position of the object,
• wherein β is a vertical phase difference between (i) a first antenna beam corresponding to the signals sent by a first transmitting antenna of the at least two switchable transmitting antennas and reflected from the object, and (ii) a second antenna beam corresponding to the signals sent by a second transmitting antenna of the at least two switchable transmitting antennas and reflected from the object,
• wherein α is a horizontal phase difference between the first antenna beam and the second antenna beam,
• wherein z is a vertical difference between the phase center of the first transmitting antenna and the phase center of the second transmitting antenna, and
• wherein λ is a wavelength of the signals sent by the first and the second transmitting antennas, and
• wherein the display device is configured to display the position of the object.