Edinburgh Napier University

  A compact fabric antenna structure integrated with a miniature electromagnetic band-gap structures (EBGs) covering the desired frequency spectrum between 2.36 GHz and 2.40 GHz of the Medical Wireless Body Networks (MBANs), is introduced. To satisfy the needs of flexible system applications, the antenna is preferably low-profile, compact, directive, and robust to the loading effect towards human body. The EBGs are attractive solutions for such requirements and provide efficient performance. In contrast to earlier documented EBG backed antenna designs, here the EBG behave not only as a shielding from the antenna to the human body, but also as a radiator. Through the dispersion diagram the band gap features of the EBG structures are confirmed. The EBGs reduces the frequency detuning due to the human body and decreases the back radiation, hence improving the antenna efficiency. The proposed antenna system has overall dimensions of 46×46×2.4 mm3. The computed and experimental results suggested that it achieves a gain of 7.2 dBi, a Front to Back Ratio (FBR) of 12.2 dB and an efficiency of 74.8 %. The Specific Absorption Rate (SAR) demonstrates a reduction of more than 95 % compared to the antenna without EBGs. Moreover, the antenna performance robustness to human body loading and bending is also studied experimentally. Hence, the integrated antenna-EBG is a good candidate for many wearable applications including healthcare devices and its related applications.