An analysis of frequency response for the blood flow of volume pulse in microcirculation

In this paper, a frequency analysis for the microcirculation model is introduced to find new microcirculation parameters in the frequency domain. By using Bode Plot of transfer function, we found two characteristic parameters of the model: damping ratio ξ and break frequency ω_n. By analyzing the variation of ξ and ω_n, it enables us to have better understanding of different states of microcirculation. At low damping, 0<ξ<1, the state of microcirculation will be better and better along with the increasing of the ω_n. At over damping, ξ≥1, the state of microcirculation will be worse and worse along with the descending of the ω_n. The results of experiments on 120 subjects are consistent with the analytical results of the model.