关于耦合谐振滤波器中耦合极性的几点讨论

对改变带有交叉耦合的耦合谐振滤波器中的耦合系数的极性而不改变滤波器的性能 ,本文给出了一个充分条件及其两个推论。这为滤波器的设计和实现带来了一定的灵活性。结合这一充分条件 ,本文还详细解释了滤波器中的耦合极性的相对性问题。最后给出了在确定耦合系数矩阵后实现滤波器时设计耦合结构的一种通用方法。

Discussion about Polarity of Coupling in Coupled-Resonator Filters

This paper proves a theorem which provides a sufficient condition for changing the polarities of coupling coefficients in coupled-resonator filters with cross couplings while the filters' performances are kept unchanged. Two corollaries are deduced from the theorem. They bring some flexibility for the design and implementation of filters. This paper also discusses in details the relativity of polarity of coupling in filters. Finally a generalized method is given for designing coupling structures of a filter after its coupling coefficient matrix has been determined.