Quarter Wave Transformer Impedance Calculator
A quarter wave transformer is used to match two transmission lines with different impedances. As the name suggests, the length of this transmission line if fixed at a quarter of the wavelength (λ/4).
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Derevation of the Quarter Wave Transformer Equation
A quarter wave transformer is used to match two transmission lines with different impedances. As the name suggests, the length of this transmission line if fixed at a quarter of the wavelength (λ/4). The wavelength can be calculated based on frequency here.
![quarter Wave formula 1](../../cdn.everythingrf.com/live/quarter_wave_formula_1.jpg)
The input impedance of a transmission line of length L with characteristic impedance Zo and connected to a load with impedance ZL:
![Quarter Wave 2](../../cdn.everythingrf.com/live/quarter_wave_formula_2.jpg)
When the wavelength is take to be a quarter wave (λ/4). This formula simplifies down to:
![Quarter Wave 4](../../cdn.everythingrf.com/live/quarter_wave_formula_3.jpg)
The Characteristic Impedance of Transmission Line is then given by:
![Quarter Wave Formula](../../cdn.everythingrf.com/live/quarter_wave_formula_4.jpg)