Design of Miniaturized Impedance Transformers Using Quarter-Wave-Like Transformers Implemented by Asymmetric Compact Microstrip Resonant Cells

摘要

This paper presents a design of miniaturized impedance transformers using quarter-wave-like transformers (QWLTs). The asymmetric compact microstrip resonant cell (CMRC) can be applied to effectively implement QWLTs, and is optimized based on its ABCD parameters to achieve a desired impedance transformation. It is found that the size reduction of approximately 52% can be achieved by using the optimized asymmetric CMRC, compared to that of the standard quarter-wave transformer (QWT), operating at 922.5 MHz with acceptable impedance bandwidth and return loss.