Pathloss modeling for in-body optical wireless communications
This work addresses the need for accurate channel models to optimize communication protocols for in-body nano-scale networks and implants, representing an incremental advancement in domain-specific modeling.
The paper tackled the problem of modeling pathloss for in-body optical wireless communications by developing a general formula for absorption coefficients of biological tissues, achieving high accuracy in modeling pathloss and penetration depth in complex tissues.
Optical wireless communications (OWCs) have been recognized as a candidate enabler of next generation in-body nano-scale networks and implants. The development of an accurate channel model capable of accommodating the particularities of different type of tissues is expected to boost the design of optimized communication protocols for such applications. Motivated by this, this paper focuses on presenting a general pathloss model for in-body OWCs. In particular, we use experimental measurements in order to extract analytical expressions for the absorption coefficients of the five main tissues' constitutions, namely oxygenated and de-oxygenated blood, water, fat, and melanin. Building upon these expressions, we derive a general formula for the absorption coefficient evaluation of any biological tissue. To verify the validity of this formula, we compute the absorption coefficient of complex tissues and compare them against respective experimental results reported by independent research works. Interestingly, we observe that the analytical formula has high accuracy and is capable of modeling the pathloss and, therefore, the penetration depth in complex tissues.