Symmetric Stripline

This is a type of Transmission Media. It is one of the reliable methods for creating a transmission line. It is a transverse electromagnetic (TEM) transmission line. This was invented by Robert M. Barrett. In case of calculating the values then you can consider the following parameters. A stripline is a W unit wide and T units thick strip of conducting material surrounded by dielectric material above and dielectric material below. This is primarily used in PCB design and routing to connect one component to another.

Properties of Stripline :

1. A flat strip of metal sandwiched between two ground planes.
2. The insulating material of the substrate forms a dielectric usually made from a Fire Retardant material called FR7.
3. It is non-dispersive.
4. Does not have a cut-off frequency.
5. Good against Electromagnetic Induction.
6. Slower propagation speed compared to Microstrip.
7. Can also support higher order TM and TE modes but this is usually avoided.
8. Attenuation due to dielectric loss is of the same form as that of any TEM lines.
9. Fields of TEM mode on a stripline must satisfy Laplace's Equation.

The Formula to Calculate Characteristic Impedance of a Symmetric Stripline : Z_{0}=\frac{60}{\sqrt{E_{r}}}ln[\frac{4H}{0.67\pi W(0.8+\frac{T}{W})}]