Power distribution and performance analysis of terahertz communication in artificial skin

Apart from the effect of path loss and signal-dependent molecular absorption noise, the capabilities of in-vivo nano-communication at the Terahertz (THz) frequencies are also strictly influenced by the distribution of power transmission in the frequency domain. In this paper, the artificial skin with different fibroblast cell densities are considered as THz communication medium; signal-to-noise ratio (SNR) and channel capacity as a function of the transmitted signal power in flat and Gaussian-shaped distribution is quantified. In addition, the achievable communication distance of THz wave inside the artificial skin is evaluated. The results show that, SNR increases sharply with the rise of the transmitted signal power from -90 dBW to -30 dBW in flat distribution, and from -90 dBW to -40 dBW in Gaussian distribution; after the critical value, there is minor improvement when further increasing the power. The achievable communication range of THz wave inside the artificial skin is strictly limited to about 1 to 2 mm, and the specific distance depends on the medium composition. Gaussian-shaped power distribution can provide higher SNR but lower capacity compared with flat distribution. The obtained results provide fundamentals in building future intra-body nanonetworks.