On the Outage Capacity of Transdermal Optical Wireless Links with Stochastic Spatial Jitter and Skin-Induced Attenuation

Abstract

The tremendous development of both optical wireless communications (OWC) and implantable medical devices (IMDs) has recently enabled the establishment of transdermal optical wireless (TOW) links that utilize light waves to transfer information inside the living body to the outside world and conversely. Indeed, numerous emerging medical applications such as cortical recording and telemetry with cochlear implants require extremely high data rates along with low power consumption that only this new technology could accommodate. Thus, in this paper, a typical TOW link is investigated in terms of outage capacity which is a critical performance metric that has so far not been evaluated for such wireless systems in the open technical literature. More precisely, an outage capacity analysis is performed considering both skin-induced attenuation and stochastic spatial jitter, i.e., pointing error effects. Analytical expressions and results for the outage capacity are derived for a variety of skin channel conditions along with varying stochastic pointing errors which demonstrate the feasibility of this cross-field cooperation. Lastly, the corresponding simulation outcomes further validate our suggestions.

Capacity Performance Analysis for Terrestrial THz Channels

“…Note also that σ n = 10 −7 A/Hz in all the above-mentioned link scenarios [20,50]. Finally, for the outage capacity estimation scenarios under investigation we have set R = 0.1 which is very common for any practical wireless communication link [33][34][35]66,67,69]. Figure 1 illustrates the average capacity evolution for the investigated THz link versus the transmitted power through a strong gamma-gamma modeled turbulent channel with either clear, rain, or fog weather conditions and moderate air humidity along with the presence of FSPL and strong ZB or NZB PE.…”

“…The instantaneous channel capacity C, which is a very critical metric for the performance of any communication system, is defined as [34,66]…”

“…A very crucial outage performance metric for the availability of any communication system is its outage capacity, C out , which refers to the capacity guaranteed for a percentage rate of (100 − R%) or, equivalently, (1 − R), of the channel realizations [39,66,67]…”