Miniaturized annular ring patch antenna for MIMO communications

This paper presents a miniaturized annular ring patch antenna (1-ARA) instead of two circular patch antennas (2-CPA) to generate higher-order mode patterns for multiple-input multiple-output (MIMO) communication system applications. With two orthogonal radiation patterns, a 2×2 MIMO communication system can be realized (pattern diversity). The proposed ferrite 1-ARA was tested using the FEKO electromagnetic simulator. It was found that the size of the proposed ferrite 1-ARA can be significantly smaller, e.g., 20 times, than that of the more recent dielectric two-stacked CPAs. Performance of the proposed Fe 1-ARA was evaluated by calculating ergodic capacity and bit error rate and compared with a conventional 2×2 MIMO system.