基于多级不对称耦合器负群延时电路研究

Research of Negative Group Delay Circuit Based on Multistage Asymmetrical Directional Coupler

提出了一种基于多级不对称耦合器结构的负群延时电路。通过合理设置耦合器的耦合系数,可以在多节耦合线耦合器的耦合端得到带宽较宽的负群延时效果,和采用集总电阻、电容元器件构成的带阻结构的传统负群延时电路相比,该电路设计全部采用分布式耦合微带线实现,集成化程度高,插入损耗小、可应用于更高的频段。此电路结构可广泛用于功率放大器前端,用以提高放大器的效率。

The paper presents a novel negative group delay （NGD） circuit base on asymmetrical couplers. By cascading couplers with appropriate coupling coefficients, we are able to synthesize negative group delay with a broad bandwidth at the coupled port of couplers. Unlike conventional NGD circuits that use bandstop structures with lumped elements, such as inductors and capacitors, to realize negative group delay, the proposed design provides a fully distributed realization of NGD circuit and has a high degree of integration, that could use in more high frequency and its return loss will be less. The circuit could widely use in the freedom of power amplifiers to develop its efficiency.