Skin exposed 5 GHz antenna safety challenges and radiation performances analysis based on method of moments

摘要

One of the recent challenges that arise in the study of small antennas is the bio-electromagnetic analysis of implantable and wearable devices for e-health applications. In this paper, a new on-body scenario for safely limits is discussed. An analysis of the electromagnetic interaction between a model of human body tissue and a wearable thin on-body antenna operating at 5 GHz frequency, is made. Based on specific absorption rate (SAR), the analysis of two considered scenarios, antenna in free space and antenna in the presence of biological tissue, is established. The method of moments and generalized equivalent circuit MoM-GEC are used for numerical modeling and are compared with a simulated and measured data. Results are investigated in terms of electric field, SAR, radiation pattern and directivity. The numerical data demonstrate a significant body absorption quantified by a local SAR distribution and an averaged SAR (1 g) of about 1.930 W/Kg. This effect matches with radiated power reduction of about 28.7 dBW/m(2). Four metrics of radiation data are discussed: the main lobe level, the main lobe direction, the angular width and the presence of side lobes.