Wearable Dual-Band Filtering Monopole Antenna for Wireless Body-Centric Communications

A wearable dual-band filtering monopole antenna is presented for wireless body-centric communications. The length and impedance ratio of the proposed dual-band monopole antenna can be applied to tune center frequencies of two radiation bands independently. To suppress radiation bands of parasitic high order modes, a U-shaped and two L-shaped slots are integrated with the monopole antenna to realize bandstop filtering responses without using additional filters. The body-antenna coupling effects are investigated by using a three-layer tissue model. The body-antenna coupling strength is inversely proportional to the body-antenna separation distance and the optimum body-antenna separation distance of one-eighth free space wavelength can be applied to wearable applications. The proposed dual-band monopole antenna has measured center frequencies of 2.45 and 5.8 GHz with the measured bandwidths of 340 and 920 MHz, respectively.