2?×?2 MIMO Asymmetric U-Shaped Nonuniform Slot Antenna for the 4G LTE Metal-Housing Mobile Handsets

摘要

A 2?×?2 MIMO antenna for metal-housing mobile handset application is proposed in this article. The polarization diversity is used to arrange the two antennas’ setup. The asymmetric U-shaped nonuniform slot antenna provides two different resonant bands are designed to be operated in long term evolution (LTE) covers lower band (698?MHz to 960?MHz) and upper band (1710?MHz to 2700?MHz). The modified type III balun is used for upper-operating band, and the open stub is used for lower-operating band, good impedance bandwidth, and radiated pattern and efficiency are shown. The isolation (S21) between the antennas is more than 20?dB, and the envelope correlation coefficient (ECC) is less than 0.02. A prototype of the proposed antenna chiselling in the metal-housing mobile handset (with 160?mm in length, 10?mm in height, and 70?mm in width) is fabricated and experimentally studied.