Wearable Beam Steering Branch Line Coupler Fed Array Antenna for WBAN Applications

This paper, introduce a wireless body area network antenna array with beam steering that is fed by a branch line coupler (BLC). The proposed BLC feeding network and the antenna are fabricated on wearable jeans substrate, and the proposed antenna operates at the ISM-I (2.45 GHz) band. The Branch line coupler fed array antenna (BLCAA) allows for 25 degrees of beam steering with a half-power beam width of 25 degrees and 35 degrees in the presence of free space and the human body, respectively. The proposed antenna's specific absorption rate was found to be 0.21 W/Kg, which complies with IEEE regulations. To assess the effect of bending on the antenna's performance, simulations and tests were conducted, revealing that the antenna's characteristics were minimally affected by bending. The BLCAA exhibits good impedance matching with high peak gain and a good radiation pattern. The simulated results are experimentally validated and found good approximation.