Getting parameters of absorbing structure based on genetic evolutional algorithm
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摘要: 对多层吸波结构中未知参数层的电磁参数进行了反演.根据传输线理论确立的多层结构电磁参数与反射/透射系数的关系,建立正向反射率计算模型,根据自由空间法原理搭建的测试平台测量得到多层吸波材料不同入射角度下的反射率信息,利用改进的遗传进化算法获取了多层吸波结构中未知参数层的电磁参数.在遗传进化过程中,采用高斯随机数代替基本遗传算法的均匀随机数,避免了传统网络参数法厚度谐振、多值性问题和基本遗传算法易陷入局部最优点的问题.与传统传输/反射法结果的比较,验证了这种方法的可靠性.这种方法同时适用于计算高、低损耗介质材料的电磁参数.Abstract: Electromagnetic parameters of unknown layer in absorbing structure were gotten. Model of calculated reflection coefficients was founded by the relation of material parameters and reflection coefficients based on transmission line theory. Reflection coefficients of different incident-angle was measured with platform based on free space method. Electromagnetic parameters of unknown layer in absorbing structure were gotten with new genetic evolutional algorithm. In the process of evolution, Gauss-s random number was used instead of uniform random number. Used this method, the problems of multi-value and thickness resonance are solved and it is avoided to get into local best value during calculation. Compared with traditional transmission/reflection method, it is proved that the method is reliably. This method can be used for both high and low loss materials.
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