An automotive radar transceiver arrangement and radar array antennas with increased angular separability

A linear radar array antenna comprising at least two superimposed subarray antennas, each subarray antenna comprising a plurality of antenna elements, where, for each subarray antenna, a plurality of antenna elements are positioned in a linear manner defined by:

• d
• ni
• =
• (
• ε
• i
• ⁢
• M
• ⌣
• i
• ⁢
• n
• +
• s
• i
• )
• ⁢
• d
• ,
• where:
• the subscript i denotes a given subarray antenna of the at least two superimposed subarray antennas, wherein i runs from 1 to q and q is a number of the at least two superimposed subarray antennas,
• εi is a sparsity factor that can be any positive integer and is used to modify the co-prime locations for the array antenna,
• M
• ⌣
• i
• =
• M
• i
• p
• i
• where Mi is a chosen coprime number that defines subarray interelement spacing, and pi is a compression factor that relates to Co-Prime Arrays with Compressed Inter-element Spacings (CACIS), and pi∈[1,Mi], such that is an integer,
• n is an integer value which indicates a given antenna element of the plurality of antenna elements and starts from zero,
• dni denotes a position of the given antenna element in the given subarray antenna,
• d is a Nyquist distance,
• λ
• 2
• ,
• where λ is a wavelength for at least one intended frequency, and
• si defines a shift distance from a zero reference, being a real number equal to or larger than zero,
• wherein for at least one subarray antenna of the at least two superimposed subarray antennas, the shift distance si is chosen to be non-zero and non-integer.