Design and Implementation of a Three-Section Transmission Line Transformer

摘要

New formulations of fundamental load impedance circuit in the Z-plane are employed to study transformers. Transformer configuration consists of three-section serial lines. The design procedures employ prototypes of transfer function, parametric modeling techniques, and optimization methods; dual-band uncorrelated frequencies of transfer function at the normalizing frequency () are studied. This transformer was designed on a PCB FR4 substrate featuring a permittivity epsilon r=4.4, a loss tangent tan=0.0245, and a thickness of h=1.6mm. The results of simulation and measurement show that complex load impedance can be matched at two uncorrelated frequencies. The values of characteristic impedances of transmission lines synthesizing the transformers are adjusted according to the autoregressive process by optimization algorithms. The experimental results are in good agreement with theoretical values.