A small-size MIMO antenna for portable devices in Bluetooth/WIMAX/WLAN/UWB applications

This paper presents a small-size multiple-input-multiple-output (MIMO) antenna for wireless portable device applications. It entirely covers the Bluetooth (2.4-2.484 GHz), Worldwide Interoperability for Microwave Access (WiMAX) (3.4-3.69 GHz), Wireless Local Area Network (WLAN) (5.15-5.825 GHz) and ultra-wideband (UWB) (3.1-10.6 GHz) operating bands. This antenna consists of two planar polygon printed monopole (PM) antennas, a rectangular slot and a triangular trim on the antenna element to lower down the low-cutoff frequency for improving the impedance matching, and a stepped ground stub to improve the isolation. Two rounded corners are simultaneously used on the ground for the impedance matching at medium-high frequency. Simulated and measured results prove that the -10dB bandwidth of this antenna is from 2.4 to 11 GHz, and the isolation is less than -15dB in the entire band. Its size is only 40×36 mm2 on a cost-effective FR4 substrate.

[1]  Feng Zheng,et al.  An Overview of Ultra-Wide-Band Systems With MIMO , 2009, Proceedings of the IEEE.

[2]  Rashid Saleem,et al.  An UWB diversity antenna array with a novel H-type decoupling structure , 2013 .

[3]  Biswajeet Mukherjee,et al.  MIMO Antenna for Bluetooth, Wi-Fi, Wi-MAX and UWB Applications , 2014 .

[4]  Ziqiang Xu,et al.  Compact Printed UWB Diversity Slot Antenna With 5.5-GHz Band-Notched Characteristics , 2014, IEEE Antennas and Wireless Propagation Letters.

[5]  Muhammad Saeed Khan,et al.  Isolation enhancement of a wideband MIMO antenna using floating parasitic elements , 2015 .

[6]  M. Sreenivasan,et al.  A Simple Ultrawideband Planar Rectangular Printed Antenna With Band Dispensation , 2010, IEEE Transactions on Antennas and Propagation.

[7]  Lizhong Zheng,et al.  Diversity and multiplexing: a fundamental tradeoff in multiple-antenna channels , 2003, IEEE Trans. Inf. Theory.

[8]  Mohammad S. Sharawi,et al.  A UWB semi‐ring MIMO antenna with isolation enhancement , 2015 .

[9]  R.G. Vaughan,et al.  Antenna diversity in mobile communications , 1987, IEEE Transactions on Vehicular Technology.

[10]  Tayeb A. Denidni,et al.  Uniplanar polarisation diversity antenna for ultrawideband systems , 2013 .

[11]  Jong-Myung Woo,et al.  A Compact Ultrawideband MIMO Antenna With WLAN Band-Rejected Operation for Mobile Devices , 2012, IEEE Antennas and Wireless Propagation Letters.

[12]  Sailing He,et al.  Ultrawideband MIMO/Diversity Antennas With a Tree-Like Structure to Enhance Wideband Isolation , 2009, IEEE Antennas and Wireless Propagation Letters.

[13]  Shuxi Gong,et al.  Compact polarization diversity ultrawideband mimo antenna with triple band‐notched characteristics , 2015 .