The role of impedance transformer is crucial in RF microwave input/output impedance matching and antenna feed network design. Impedance transformer are primarily used as bridging network between two component with different input impedances. Quarter-wave impedance transformer or λ/4 impedance transformer is very popular in electrical engineering .
The relationship between the characteristic impedance, Zo, Zin and load impedance, ZL is: Z0=sqrt(Zin*ZL).
Below is one simulated design in ADS (Advanced design system) that transfer 100 ohm impedance to 50 ohm impedance .
Simulated S-Parameter data