| Abstract: | A method to significantly increase the gain and reduce the mutual coupling of microstrip multiple‐intput multiple‐output (MIMO) antenna based on metamaterial concept is presented. The μ‐negative and ε‐negative features of the proposed modified peace‐logo planar metamaterial (MPLPM) and two‐sided MPLPM (TSMPLPM) structures are calculated. The antenna structure consists of eight MPLPM slabs and two TSMPLPM, which are embedded in azimuth plane of a MIMO antenna vertically. The dimensions of MIMO antenna are 28 × 16 × 6.3 mm3 at 40 GHz. As a result, a compact MIMO antenna is simulated in comparison with primary microstrip structures. The corresponding return‐loss of the antenna is better than 10 dB over 34.5 to 45.5 GHz for Ka‐band applications. Good consent between the measured and simulated result is tacked. The maximum simulated gain of the structure is 15.5 dB at 40 GHz, creating a maximum gain improvement of 11.5 dB in comparison with a MIMO antenna without any metamaterial combinations. The value of the insertion‐loss (isolation) is 33 dB, which has improved by more than 25 dB compared to the conventional sample. |
