基于有限积分法的电磁兼容吸波材料反射率的建模仿真
FIT-based simulation of reflectivity of absorbing materials for electromagnetic compatibility

针对电磁兼容吸波材料反射率试验测试成本较高、理论方法难以精确预测的问题,提出了基于有限积分法的吸波材料反射率的建模仿真方法.使用该方法计算了矩形同轴测试装置空载反射系数,以及分别加载铁氧体瓦和角锥泡沫吸波材料后的反射系数.吸波材料的介电常数和磁导率使用二阶通用色散模型进行拟合.对于铁氧体瓦,仿真得到的反射率略优于实测值,与产品提供的反射率曲线相比,在谐振点处相差10 dB.对于角锥泡沫吸波材料,仿真结果与实测值在有效测试频率范围内相差7 dB.对仿真结果与实验结果的差别进行分析,证明了该方法的可行性.
Considering the high cost in experimental measurement and the difficulty of accurate prediction by theoretical method, a simulation method based on finite integration technique(FIT)is proposed to obtain the reflectivity of absorbing materials for electromagnetic compatibility. By using this method, the reflectivity of rectangle coaxial device without loading, and the reflectivity with loading either ferrite tiles or pyramid foam absorbers are calculated. The general second-order dispersion model is used to fit the permittivity and permeability of the absorbing materials. For ferrite tiles, the reflectivity from simulation results is slightly superior to experimental results, and the difference of reflectivity around the resonance frequency is 10 dB between the simulation results and the reflectivity curve provided by the producer. For pyramid foam absorbers, the difference is only 7 dB within effective testing frequency range. The difference of the results from simulation and experiment is analyzed. The practicability of this method is verified