A Wideband Printed Dual-Antenna System With a Novel Neutralization Line for Mobile Terminals

A wideband printed dual-antenna system for mobile terminals is presented. The dual-antenna, consisted of two symmetric antenna elements and a neutralization line (NL), is printed on a printed circuit board. The antenna element is an F-like monopole with a grounded branch. The working mechanism of the dual-antenna is analyzed based on the
${ S}$
-parameters and the surface current distributions. A prototype shows the measured
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10-dB impedance bandwidth is 1.09 GHz (1.67–2.76 GHz) and the measured mutual coupling is lower than
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15 dB at the 1.7–2.76-GHz bands. It covers the GSM1800, GSM1900, UMTS, LTE2300, LTE2500, and 2.4-GHz WLAN bands. The radiation patterns are measured, and the diversity performance is evaluated .