用频设备带外多频电磁辐射三阶互调阻塞效应测试与建模评估方法

Testing and Modeling Evaluation Method of Third-Order Intermodulation Blocking Effect by Outband Multifrequency Electromagnetic Radiation for Spectrum-Dependent Equipment

针对用频设备复杂电磁环境适应性试验评估的技术需求,从场路线性耦合、电路非线性响应机理出发,引入三阶互调阻塞干扰因子,建立了三阶互调阻塞效应模型.理论推导与实验测定相结合,给出了模型参数的确定方法、三阶互调阻塞效应建模评估流程,以通信电台作为受试设备进行了实验验证.结果表明:利用在特定工作频率下测试确定的用频设备三阶互调阻塞干扰因子,假定其不随辐射干扰频偏变化,依据用频设备单频电磁辐射阻塞临界干扰场强变化曲线和环境电磁场频谱分布参数,能够准确评估用频设备的三阶互调阻塞效应,误差小于1dB.

Aiming at the technical requirements of the complex electromagnetic environment adaptability test and evaluation for the spectrum-dependent equipment,starting from the linear coupling of field with circuit and the nonlinear response mechanism of circuit,the third-order intermodulation blocking effect model is established by introducing the third-order intermodulation blocking interference factor.Combining theoretical derivation and experimental measurement,the method of determining model parameters and the process of modeling and evaluation of third-order intermodulation blocking effect are given,and the experimental verification is carried out using the communication radio as the equipment under test.The results show that,using the third-order intermodulation blocking interference factor of the spectrum-dependent equipment tested at a specific working frequency,assuming that it does not change with the frequency offset of the radiated interference,according to the variation curve of the critical interference field strength of the single frequency electromagnetic radiation blocking for the spectrum-dependent equipment and the distribution parameters of environmental electromagnetic field spectrum,the third-order intermodulation blocking effect of the spectrum-dependent equipment can be accurately evaluated,and the tested error is less than 1dB.