The simulation of the frequency-dependent effective permittivity for composite materials

Increasing our ability to understanding dielectric properties of composite materials is of central importance in many scientific and technological applications. A two dimensional model of two phase composite materials has been described, and it's effective permittivity have been simulated based on FEM method and S parameters retrieval algorithm. Results show that the effective permittivity of periodic model is good agreement with Maxwell Garnett rule, and the real part and imaginary part of effective permittivity of random model increases with frequency. This result is counterintuitive due to both inclusions and host are lossless materials. How to understand this effect is a subject of our future research.