On-board small-size printed LTE/WWAN mobile handset antenna closely integrated with system ground plane

Abstract

An on-board uniplanar printed mobile handset antenna with a small size of 15 × 30 mm2 for 8-band long term evolution/wireless wide area network (LTE/WWAN) (698–960/1710–2690 MHz) operation is presented.The antenna is a spiral monopole coupled with a long parasitic shorted strip. The spiral monopole has a length of 78 mm (about 0.25 wavelength at 950 MHz), while the shorted strip capacitively excited by the spiral monopole has a length of 125 mm (close to 0.25 wavelength at 700 MHz). The spiral monopole is encircled by the shorted strip so that the antenna has a compact configuration to fit in a small no-ground portion at the corner of the bottom edge of the main circuit board in the mobile handset. In addition, the antenna is closely integrated with the system ground plane on the main circuit board and is spaced by a small distance of 0.5 mm to the nearby system ground plane. This leads to compact integration of the on-board LTE/WWAN printed antenna on the main circuit board of the mobile handset. Results of the proposed antenna including its specific absorption rate and hearing aid compatibility behavior are presented and discussed. The antenna is about the smallest for the on-board all-printing LTE/WWAN handset antennas that have been reported for the present. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1336–1343, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25961