Decoupled Dual-Antenna With Three Slots and a Connecting Line for Mobile Terminals

In this letter, a wideband printed dual-antenna for mobile terminals is presented. The dual-antenna consists of two symmetric antenna elements, a connecting line (CL), and three slots. The antenna element is an L-like monopole with a grounded branch, and the two antennas are connected by a narrow line. The three slots and connecting line not only reduced the mutual coupling, but also improved the reflection coefficient within a wide frequency band. Different slot can adjust different frequency band independently. The working mechanism of the three slots is analyzed based on the S-parameters and surface current distributions. A prototype shows that the measured -10 dB impedance bandwidth is 1.01 GHz (1.71-2.72 GHz), and the measured mutual coupling is lower than -15 dB at 1.68-2.7-GHz bands, which covers the GSM1800, GSM1900, UMTS, LTE2300, LTE2500, and 2.4-GHz WLAN bands. The radiation patterns are measured, and the diversity performance is presented.