Tag: smith chart

Impedance matching of the WPT coil

Hello, I will explain how I matched input impedance of the WPT coil to 50 Ohm. Please look at the following picture. You can see that SMA cable is directly connected with the feed coil. Let’s see the frequency characteristic properties of this WPT coil. Frequency range is between 1 MHz and 27 MHz. So the center frequency is 14 MHz (=0.5*(1+27) MHz) that is the resonant frequency of this WPT coil. In the following picture, Blue line shows S11 [dB], Pink line shows VSWR, Green line shows Re(Zin), Yellow line shows Im(Zin) and Red line shows the Smith chart of S11. We can easily find that the impedance is […]