A compact dual-band MIMO planar antenna

This paper presents a compact dual-band MIMO planar antenna that is designed particularly compatible to the IEEE 802.11n Mobile Wireless Access Network Standard. In order to reduce the size, the antenna radiator element is organized with a winding tree-type monopole, and the two branches in the tree structure are put together to produce the two designated frequency bands of 2.4GHz and 5.2GHz respectively. The radiator element is accompanied with a coplanar feeding network. The MIMO antenna contains two antenna elements separated by one-fifth of the wavelength of the lower frequency band. Further, two half-wavelength meander-line resonator corresponding to the two frequency bands are placed between the antenna elements to achieve an excellent mutual coupling performance. In addition, the characteristics of small size, nearly omnidirectional coverage in antenna radiation pattern and moderate radiation gain make the proposed MIMO antenna entirely applicable to the mobile wireless access applications. The high frequency computer aid design has been utilized to optimize the proposed MIMO antenna performance, and have shown to be well-matched to the measured results of the fabricated prototype.