This paper presents the design of a flexible antenna using planar dipole with a reflector to achieve optimal radiation efficiency and low specific absorption rate (SAR) when the antenna is placed directly over the skin of body model. The antenna is designed for the 2.45 GHz frequency band. The parametric analysis of the proposed antenna is carried out. The proposed antenna achieves stable on-body performance: |S11| varies from -16.05 dB (on skin) at 2.47 GHz resonant frequency to -16.40 dB (on skin) at 2.47 GHz resonant frequency to -16.40 dB (in free space) at 2.44 GHz resonant frequency. It was found that the maximum 1 g average SAR value is only 0.23 W/kg for an input power of 100 mW when the antenna is placed directly over the skin of a three-layer body model, and radiation efficiency is 20.5%. The measured results are presented to demonstrate the validity of the proposed antenna.
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