Impact of anatomical variability on the wireless power transfer to intra-abdominal implants

We study the impact of the anatomical variations of the human body model on the wireless power transfer link for passive intra-abdominal implants. We categorically analyze the power transfer link for four body sizes ranging from 21 to 36 inches of radial dimensions with an implant depth of 48.5 mm to 101 mm with promising received power level corresponding to maximum SAR compliant transmission power fed to an around-the-body transmitting antenna. In this assessment, the transducer power gain of the wireless link varied from-2.65 to-10.84 dB. We also evaluated the robustness of the system subject to ±20 percent variation in the relative permittivity and loss tangent and the results show the impact to be only ±0.26 dB variation in the transducer gain. Lastly, we analyze the performance of the system under various degrees of angular misalignment between the transmitter-receiver antennas.