Radiation Pattern of an UWB Wearable Antenna: A Preliminary Study

Inhomogeneity of the propagation medium in body area networks could have a great impact on the sensor node’s antenna characteristics. This in turn could affect the quality of the communication links unless the impact of human body has been properly considered during the design phase of the antenna. In this paper, we investigate the impact of the antenna’s placement and its distance from the body surface on its radiation pattern and the resulting specific absorption rate (SAR). It is shown that the antenna placement could affect the in-body radiation pattern of the antenna, and therefore the value of SAR. Regulatory restrictions on SAR would then translate to maximal allowable power for the transmitter. This maximal allowable value could depend on the exact location of the antenna with respect to the body surface.