通信系统无源非线性引起的互调干扰

Intermodulation interference due to passive nonlinearity in communication systems

分析了通信系统中无源互调干扰产生的基本理论、产生机理、减小措施以及分析与建模,总结了无源互调干扰的探测、定位和测量方法.认为无源互调产物是多载波通信系统的重要干扰源,包括接触非线性和材料非线性在内的无源非线性是这种干扰的根本起因.目前关于无源互调幅度的分析计算还局限在幂级数方法上,今后关于无源互调问题的研究重点将是无源非线性物理模型的建立,以及由容易测量的低阶无源互调幅度预测高阶幅度更为有效方法的研究等方面.

An overview on the basic theory, the generation mechanism, the mitigation measure and the analysis and modeling of passive intermodulation (PIM) interference in communication systems is given. The detecting and locating methods and the measurement of PIM interference are discussed. It is indicated that PIM products are important interference source in multi-carrier communication systems and passive nonlinearity including contact nonlinearity and material nonlinearity is the essential origin of such interference. Present analysis and calculation methods for PIM are limited to power series method. At further study attentions should be paid to the establishment of the physical model of passive nonlinearity and more efficient methods for predicting the amplitude of higher order PIM products with that of lower order products which can be measured more easily.