A quad-band (3.5, 5.8, 7.5 & 8.08 GHz), low profile, low Specific Absorption rate (SAR), and circularly polarized (3.5, 7.5, 8.08 GHz) wearable textile antenna (50x30x1 mm3) integrated with a triple-band zero reflection phase Artificial Magnetic Conductor (AMC) surface is presented. The designed standalone antenna exhibits low SAR with 10 mm separation for 0.5 W input power and radiation performance with a gain of >5 dB and Front to Back Ratio (FBR) (<10 dB) at all operating frequencies. The AMC unit-cell is synthesized using PDMS (Polydimethylsiloxane) with footprint of 20×20×1 mm3 to operating at 3.5, 7.5, and 8.08 GHz respectively with in-phase reflection. The designed 3×3 AMC reflector is integrated to improve the radiation performance of the designed antenna with gain to >7 dB, FBR to >10 dB, and withstanding low SAR at increased input power compatibility at separation (d=3 mm) from the body surface. The designed AMC transforms the radiation pattern from omnidirectional to directional with improved FBR, reduced back radiation with low SAR (<0.504 W/kg). The proposed AMC integrated antenna also providing mechanical feasibility in terms of handling the frequency detuning due to bending and the human-body loading feature makes it suitable for wireless body area networks (WBAN) applications.
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