Microstrip Transmission Line
We will use Microstrip Trnasmission Line for filter design, stub matching design, and other applications. All microstrip impedance calculations are approximations, so you'll find lots of different versions, based on the thicknesses of the substrate and copper, and also if there is a covering over the top. For our purposes, these will all be pretty close.
Here are some useful resources for Microstrip:
Microwave Engineering, by David Pozar, Chapter 3.8 Download Microwave Engineering, by David Pozar, Chapter 3.8
Microstrip Calculator from EMLab Links to an external site.
Microstrip wavelength calculator from Pasternack Links to an external site.
Practical Considerations from Microwave101 Links to an external site.