微波频段金属接触非线性引起的无源互调功率电平的分析和预测

微波频段由于金属接触非线性引起的无源互调可对系统性能造成严重影响。本文讨论了微波频段金属接触非线性的主要机理和简化模型 ,推导了双正弦输入时任意奇数阶无源互调幅度的多项式表示式和矩阵表示式 ,并给出了三阶和五阶无源互调功率的表示式。作为应用实例 ,利用微波频段金属接触引起的低阶无源互调功率电平的测量值 ,对其高阶无源互调功率电平进行了预测 ,通过比较发现 ,预测结果与测量结果基本一致

The Analysis and Prediction of the Power Level of PIM Due to Metallic Contact Nonlinearity at Microwave Frequencies

Passive intermodulation (PIM) products due to metallic contact nonlinearity at microwave frequencies can have severe effects on system performance. The principal mechanism and simplified model of metallic contact at microwave frequencies are discussed. The polynomial and matrix representations for arbitrary odd order PIM amplitudes are derived. General mathematical formulas regarding the third order and fifth order PIM power levels are given. As an example, prediction of the fifth order PIM power level with third order measured values is carried out by computer program. The calculated values are compared with experimental results, indicating that the predicted result practically agrees with the measured one.