A Compact MIMO antenna System with Three Closely Spaced Multi-band Antennas for WLAN Application

Abstract

In this paper, a MIMO antenna system is designed for multi-band Wireless local area network (WLAN) application with standards of IEEE 802.11a/b/g/j. As shown in Fig. 1, three printed antennas, each covering the frequency bands of 2.45, 4.9, 5.25, 5.75 GHz, are designed in a compact area of 1 x h = 48mm x 28mm, which is a suitable size for PC card application. The measurement results show 10-dB return loss with bandwidth more than 350MHz in the 2.45GHz frequency band and more than 1.2GHz in the 5GHz frequency band. In addition, the radiation pattern of these antennas is complementary in all directions to realize pattern diversity. The coupling between any two of these antennas is below -8.5dB. The proposed antenna has the properties of good performance, compact size, low profile, and low cost. Hence, it is suitable for practical MIMO applications in a WLAN system.