Calculation of Material Permittivity and Permeability Based on Trust Region Algorithm

The permittivity and permeability are important parameters to characterize the electromagnetic characteristics of materials. In order to solve the problem of the limitation of material processing shape and accuracy in the calculation, this paper proposes a method to calculate the complex permittivity and permeability of materials by using CST simulation, trust region algorithm and measured S parameters based on rectangular waveguide method (one of transmission/reflection method). In this paper, the performance of four common CST optimization algorithms in this problem is compared, and the effectiveness of the method is verified by using PTFE material.