Your stated equation for impedance relates to 'lumped' reactive components: transmission lines do not posses reactive components of that nature: the L and C are uniformly distributed throughout the line's length. Hence, that equation is not applicable for transmission lines.
The characteristic impedance (Zo) of a transmission line is independent of its capacitance and inductance. It is dependent on the physical size of the conductors, their separation and the nature of the material between them. Zo is not determined by the d.c. resistance of the line.
This link provides a simplified explanation:
http://www.allaboutcircuits.com/vol_2/chpt_14/3.html
Alternatively, you can learn all about transmission lines in much more detail in most text books on radio theory.
Al.
The characteristic impedance (Zo) of a transmission line is independent of its capacitance and inductance. It is dependent on the physical size of the conductors, their separation and the nature of the material between them. Zo is not determined by the d.c. resistance of the line.
This link provides a simplified explanation:
http://www.allaboutcircuits.com/vol_2/chpt_14/3.html
Alternatively, you can learn all about transmission lines in much more detail in most text books on radio theory.
Al.
