Analysis of Shielding and Discontinuous Phantom Medium Effect on the Performance of Fat-Intra Body Communication System

This paper presents the design, optimization, and detailed analysis of a wearable fat intrabody communication (Fat-IBe) system based on resonator antennas, specifically tailored for biomedical applications. Fat- IBC uses the low dielectric loss properties of human fat tissue, as a wave guide between the skin and muscle layers. This technique facilitates continuous communication among wearable, implanted, and semi-implanted biomedical devices, supporting seamless data exchange within body area networks (BAN). The proposed Fat-IBC system is designed to operate in the 2.40-2.48 GHz industrial, scientific, and medical (ISM) frequency band, widely recognized for medical telemetry. The proposed system employs a resonating antenna designed using a planar circular spiral with an enclosed notch, excited by a loop antenna. For the numerical simulations, a multi-layer human tissue model, comprising skin, fat, and muscle, is utilized to optimize the performance of the antenna resonator. To ensure bio-compatibility and prevent direct contact with human tissue, a polydimethylsiloxane (PDMS) coating surrounds the the structure. The architecture of the system incorporates two identical antennas that act as transmitting (Tx) and receiving (Rx) elements. These resonators are strategically placed at various distances on the tissue model to evaluate energy transmission efficiency. To mitigate energy losses and minimize surface wave propagation over the skin, the antenna is shielded by ferrite and copper tape. The feasibility of the proposed Fat- IBC system is established through comprehensive numerical simulations and validated by experimental studies, demonstrating its potential for high-performance biomedical communication.