Influence of the cardiac activity on the surface impedance of a multilayer model

Biological tissues are seen as multilayer structures. We will use in this article a model with three layers: skin, fat and muscle. This structure may be related to a pattern of cascaded lines where each tissue has its own characteristic impedance, permittivity and conductivity. This structure allows us to solve the problem of the surface impedance. Each layer is similar to a line of characteristic impedance. The impedance of the first layer will be transformed as soon as one progresses to the surface. This article represents, first, a detailed study of the electrical properties of a stratified propagation medium, and secondly, a study of the variation of the surface impedance according to the cardiac activity.