FRACTAL KOCH MULTIBAND TEXTILE ANTENNA PERFORMANCE WITH BENDING, WET CONDITIONS AND ON THE HUMAN BODY

A multiband Fractal Koch dipole textile antenna is proposed for wearable applications. The antenna is designed to operate at 0.9 GHz, 2.45 GHz and 5.8 GHz. Denim materials as the substrate are selected aiming to obtain robustness, flexible and lightweight textile antenna. The antenna model is designed, simulated, optimized and analyzed using Microwave Studio CST software. Two types of multiband antenna prototypes are fabricated and evaluated with different conducting elements (Shield It fabric and copper foil tape). Antenna performance is observed in term of return loss, bandwidth, radiation pattern and realized gain. Three different comprehensive analyses are taking into considerations which are measurement antenna with different bending sizes, on-body measurement and under wet condition. The antenna performances are evaluated based on resonant frequency (fo) and bandwidth (BW). The antennas performance with bending on the human body (arm & forearm) is compared and investigated. A suitable placement on the body has been discovered between chest and backside of human body. The antennas have also been tested under wet conditions to ensure the stable characteristic under the influence of water.