# Reflection coefficient and transmission coefficient formula,definition

This page describes Reflection coefficient vs Transmission coefficient definitions. It mentions Reflection coefficient and Transmission coefficient formula.

Transmission lines is characterized by basic three components Resistance (R), inductance (L) and Capacitance (C) as shown in the following figure. It is one of the way to transport RF energy.

Following are the types of transmission lines.
•  Parallel Line
•  Gas Filled Coaxial line
•  Coaxial line(standard)
•  Coaxial Line(Air Articulated dielectric)
•  Parallel Line(Shielded)
•  Double shielded coaxial Line
•  Microstrip line, READ MORE >>

Both reflection and transmission coefficients are related to transmission line.

## Reflection coefficient

The Reflection coefficient measures amplitude of reflected wave versus amplitude of incident wave. The reflection coefficient is defined as ratio of reflected voltage wave amplitude to incident voltage wave amplitude i.e. Er/Ei .
The Reflection coefficient formula in terms of impedances can be expressed as below.

In the formula Z0 or Zs is designated as Characteristic Impedance which is equal to Sqrt((R+jWL)/(R+jWC)).

## Transmission coefficient

The Transmission coefficient measures amplitude of transmitted wave versus amplitude of incident wave. The transmission coefficient is defined as ratio of transmitted voltage wave amplitude to incident voltage wave amplitude i.e. Et/Ei Transmission coefficient formula in terms of impedances can be expressed as below.