A multi-band planar antenna for biomedical applications

We present the design of a compact tri-band adhesive planar antenna which operates as a gateway for biomedical applications. Operating in the Industrial, Scientific and Medical (ISM) band (2.4–2.5 GHz), the Institute of Electrical and Electronics Engineers (IEEE) 802.15.6 Wireless Body Area Network Ultra-Wide Band (WBAN UWB) (3.1–10.6 GHz) and the IEEE 802.11 Wireless Local Area Network or WLAN (WLAN) band (5.15–5.725 GHz), the antenna is useful in the context of body-signal monitoring. The ISM band is used for in-body communication with the implanted medical devices, whereas the WBAN and WLAN bands are for off-body communication with the base station and central medical server, respectively. We have designed our antenna to operate at 2.34/3.20/4.98 GHz. The simulation results show that the antenna has 10 dB bandwidths of 420 MHz (2.07–2.49 GHz), 90 MHz (3.16–3.25 GHz), and 460 MHz (4.76–5.22 GHz) to cover the ISM, WBAN, and WLAN bands, respectively. The proposed antenna is printed on a flexible Rogers RT/duroid 5880 epoxy substrate and it occupies a compact volume of 24 × 24 × 0.787 mm. The designed antenna is simulated using HFSS and the fabricated antenna is experimentally validated by adhering it to a human skin. The simulated and measured performance of the antenna confirms its omnidirectional radiation patterns and high return losses at the three resonant bands.