[[File:RF22.png|thumb|320px|Associating the s11 data on the Smith Chart with line segment lengths at the fixed frequency of 2GHz.]]
From the transmission line theory, the input impedance and input reflection coefficient of your basic transmission live circuit can be expressed as:
<math>Z_{in} = Z_0 \frac{Z_L + jZ_0 tan \beta L}{Z_0 + jZ_L tan \beta L}</math>
and its input reflection coefficient is given by:
<math>\Gamma_{in} = \frac{1 - \zeta e^{-2j \beta L}}{1 + \zeta e^{-2j \beta L}}</math>