Chip-inductor-embedded small-size printed strip monopole for WWAN operation in the mobile phone

Abstract

A simple small-size printed strip monopole embedded with a chip inductor for covering ail the five operating hands of GSM850/900/1800/1900/UMTS for wireless wide area network (WWAN) operation in the mobile phone is presented. The antenna consists of a chip-inductor-embedded longer radiating strip and a shorter radiating strip. With a 10-nH chip inductor embedded, the longer radiating strip has a length of about 46 mm only (about 0.14 wavelength at 900 MHz), yet supports a wide resonant mode at about 900 MHz for the antenna's lower band to cover GSM850/900 operation. The shorter radiating strip has a length of about 30 mm (about 0.2 wavelength at 2000 MHz) and provides a wide resonant mode at about 2000 MHz for the antenna's upper band to cover GSM1800/1900/UMTS operation. With the five operating bands covered, the two radiating strips occupy a small printed area of about 350 mm2 on the system circuit board of the mobile phone. Details of the proposed antenna are described, and the specific absorption rate results of the antenna are also analyzed. © 2009 Wiley Periodicals, Inc.