A Novel Graphical Method For Dual-Frequency Two Sections Transformer

The most useful transmission-line construct is used to realize impedance matching at dual-frequency. The usual algebraic method is to solve the transmission equation which is precise but lack of intuition. A novel graphical method which is simple, intuitive and has explicit physical meaning is proposed to solve the matching problem. The parameters can be determined by simple geometrical relationship. Simulation and experimental results show that the proposed method is convenient, precise and can be used to extend bandwidth as well.