• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.10
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• pp.1117-1127
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• 2012

In this paper, the monopole antenna for satisfying GSM900/DCS1800/PCS1900/UMTS2100 services is designed. We can get the characteristic of the low frequency bands by connecting the front patch to the back patch of the antenna and get the low frequency resonance band using a front patch slit. The proposed antenna total volume is $40{\times}98{\times}1.6\;mm^3$, and it is designed on the FR-4 substrate having a relative dielectric constant of 4.4. As measurement result after fabrication, showed that the resonant frequency bandwidths are 156 MHz(828~984 MHz), 708 MHz(1.476~2.184 GHz) based on the return loss of 10 dB, and the radiation patterns show as the omnidirectional shapes for the E-field and H-field. For analyzing the human effects, the proposed antenna is mounted on the mobile-phone case. The averaged peak SAR over 1 g and 10 g is simulated and measured when the input power is 0.25 W. We have checked the variation of the SAR values when the antenna is mounted 4 different directions, then checked the direction having a relatively higher SAR. The results also satisfied the limiting SAR values which are 1.6 W/kg and 2.0 W/kg averaged over 1 g and 10 g tissues respectively.