2-D antenna array geometries for MIMO radar imaging by Digital Beamforming

In general, two-dimensional radar imaging applications, which require angular information in azimuth and elevation, use full planar antenna arrays. If orthogonally arranged transmit and receive arrays are used instead, the angular resolution equals that of a radar system using only a single antenna on the transmit and a full antenna array on the receiver side or vice-versa. This paper evaluates the influence of different antenna array configurations on the angular resolution capability by means of a 24GHz Digital Beamforming radar system. Besides the so-called inverted T-shaped antenna arrangement, various array geometries are discussed. Compared to the full planar antenna array the introduced geometries provide better angular resolution, while allowing for a highly reduced number of antennas, saving space and cost. Each presented antenna array is realized in hardware and the angular resolution capability is evaluated by means of a 24 GHz Digital Beamforming radar system.