An inverted <scp>L</scp>‐strip loaded ground with hollow semi‐hexagonal four‐element polarization diversity <scp>UWB‐MIMO</scp> antenna
V. Balaji, Tathababu Addepalli, Arpan Desai, Anveshkumar Nella, Truong Khang Nguyen
Abstract
Abstract A four‐element multiple‐input‐multiple‐output (MIMO) antenna with modified substrate geometry is proposed. The antenna comprises a hollow semi‐hexagonal‐shaped conductive element on the top with the modified ground plane geometry. Polarization diversity and isolation are achieved by replicating the elements orthogonally. The L‐shaped part is removed from all the sides of the substrate in the proposed four‐element antenna structure. This makes the structure compact and helps in accommodating the antenna within compact electronic gadgets. Modified ground plane consisting of partial ground, semi ellipse slot, and inverted L strip helps the antenna in achieving wide bandwidth spanning from (139.31%) 2.84 to 15.88 GHz covering UWB (3‐10 GHz), X (8‐12 GHz), and Ku band (12‐15.88 GHz) applications. The antenna achieves a size of 0.55 λ × 0.55 λ mm 2 (lowest frequency) which is printed on FR4 substrate. The antenna attains wide impedance bandwidth, Omni‐directional pattern, isolation >16 dB, ECC < 0.07, average gain >4 dBi, and radiation efficiency in the range of 78% to 89% making the MIMO antenna suitable for portable applications.