Hybrid dual‐antenna for the 3.6‐GHz LTE operation in the tablet computer

Abstract

ABSTRACTA hybrid dual‐antenna formed by an inverted‐F antenna (IFA) and an open‐slot antenna (OSA) for the 3.6‐GHz LTE operation (3.4–3.8 GHz) in the tablet computer is presented. The dual‐antenna is printed on a 0.8‐mm thick FR4 substrate and has a compact planar structure of 4 × 30 mm2. The dual‐antenna comprises a clearance region wherein the IFA is disposed and a metal pad wherein the OSA is embedded. The IFA's shorting strip is grounded through the metal pad to the device ground plane, so that an integrated compact dual‐antenna structure is obtained. As the IFA and OSA have different excitation mechanisms (electric‐current excitation on the IFA vs. magnetic‐current excitation on the OSA), the two antennas are expected to have different near‐field characteristics, thereby leading to decreased coupling. The proposed dual‐antenna has a measured isolation of better than about 12 dB over the operating band. The IFA and OSA have measured antenna efficiencies of about 72%–86% and 57%–78%, respectively. Good envelope correlation coefficient of less than 0.1 is obtained. Over the operating band, the ergodic capacity of the dual‐antenna is calculated to be about 9.8–10.6 bps/Hz. Details of the proposed dual‐antenna are presented. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2592–2598, 2015