The comparison of the near field beam patterns of 1D-CR MIMO and 2D-CR MIMO arrays

The focusing capabilities for one dimensional (1D-CR MIMO) and two dimensional circularly rotating multiple input multiple output (2D-CR-MIMO) arrays in different media are investigated. Impact of the position of the focusing point on the beamwidth and sidelobe structure is investigated. Impact of the medium (dielectric permittivity and ohmic losses) on the focusing capabilities is studied. For focusing point located at the edge position, within non or low conductive media, the -3 dB main beam width for both arrays become wider. In the same media, the form of the side lobes for 2D-CR MIMO array exhibit a spreading form while those for 1D-CR MIMO array show a spreading and periodic form. Within the high conductive medium, side lobes are concentrated around virtual elements which have a relatively narrow geometrical angle to the focusing point.