生物组织介电测量分析计算模型对比研究

针对生物组织介电特性高频同轴测量几种常用分析计算模型,在100 MHz~1 GHz 频段对不同浓度NaCl 溶液的介电特性进行实测计算,在适用范围、分析计算复杂性、准确性和稳定性等方面对这些模型进行对比研究。实际测量计算结果显示:含辐射项的等效电路模型计算误差较低,计算稳定性较高,对确定其模型参数的标准物要求较高;不含辐射项的等效电路模型易于理解、计算简单,但计算精度有待提高,计算结果受被测物、测量频率的影响较大,且同样需要较好的标准物确定其参数;准静态场分析模型不需要标准物确定参数,但模型分析较为复杂,计算耗时较高,且计算结果稳定性不足。本研究结果将为生物组织介电特性高频同轴测量分析计算模型的选用提供可靠参考。

The Comparative Study on Analysis and Calculation Models of The Coaxial Measurement of Dielectric Properties of Biological Tissue in High Frequency

In this paper, the dielectric properties of NaCl solutions with different concentrations are measured and calculated by several commonly used analysis and calculation models of the coaxial measurement of dielectric properties of biological tissue in the frequency range of 100 MHz to 1 GHz. Based on the results, these models are compared in terms of scope of application, analysis and calculation complexity, accuracy and stability. According to the actual measurement results, the calculation error of the equivalent circuit model with radiation term is low, and the calculation stability is high. But it requires the high standard materials for determining the model parameters. The equivalent circuit model without radiation term is easy to understand and simple to calculate, but the calculation error needs to be improved. It means that the calculation result of this model is greatly affected by the measured object and the measurement frequency, and the better standard materials are also required to determine its parameters. The quasi-static field analysis model does not require the standard materials to determine the parameters, but the analysis process of these models is more complicated, the calculation is timeconsuming, and the stability of the calculation results is insufficient. In summary, based on the results of this study, it can provide a reliable reference for the selection of the analysis and calculation models for the high-frequency coaxial measurement of the dielectric properties of biological tissues.