Mutual Coupling Reduction of a Dual-Band Antenna Array Using Dual-Frequency Metamaterial Structure

摘要

Dual-band antenna is an enabling component for wireless local area network (WLAN) communication systems. One of the challenges for improving the communication quality in dual-band multiple-input multiple-output (MIMO) system is to develop low coupling MIMO antenna array with compact size. In this paper, an isolation enhanced two-element MIMO antenna array with dual-frequency decoupling structure is proposed for operating at the upper and lower WLAN bands. The proposed dual-frequency decoupling structure is realized by an array of two columns of metamaterial structures with unique electromagnetic resonance characteristic. The property of the designed metamaterial array is analyzed and integrated between the elements of a two-element patch antenna array to reduce the mutual coupling. The performance of the dual-frequency patch antenna array is verified by the simulation and measurement, respectively. The experimental results show that the proposed dual-frequency MIMO antenna array has an isolation enhancement about 15dB at 2.4GHz and 9dB at 5.25GHz, respectively. Moreover, the proposed dual-band MIMO antenna has a smaller size and good directional radiation patterns, making it promising for WLAN applications.