Multi-layer Intrabody Terahertz Wave Propagation Model for Nanobiosensing Applications

Enabling wireless communication between intrabody nanosensors and wearable devices can transform the field of nanobiosensing and, ultimately, lead to revolutionary healthcare systems. Recently, it has been demonstrated that such communication can occur at Terahertz (THz) band frequencies (0.1-10 THz). For the time being, existing studies are focused on characterizing the propagation of THz waves in a uniform medium. However, in a practical system, the THz waves will traverse different body tissues as they go in/out of the body. In this paper, the propagation of THz waves across human tissues is analytically modeled and numerically analyzed. More specifically, an impedance model that accounts for the discrepancies and the thicknesses of the human tissue layers is developed to allow us to predict the loss encountered as the wave propagates through the human body at THz band frequencies. The results show the necessity of accounting for the lost power due to multi-layer reflection in order to formulate a complete intrabody communication model. At the same time, the viability of utilizing the THz band for developing a feasible intrabody communication link is demonstrated.