Transmission line must be matched to the load to ______.

It is always desirable to have a perfectly matched load for maximum power transfer, i.e. ZL = Z0

Concept:

The reflection coefficient of the transmission line at the load is given by:

\({\rm{Γ }} = \frac{{{{\rm{Z}}_{\rm{L}}} - {Z_0}}}{{{Z_L} + {Z_0}}}\)

ZL = Load impedance

Z0 = Characteristic Impedance

For a perfectly matched load:

ZL = Z0

The reflection coefficient is:

\({\rm{Γ }} = \frac{{{{\rm{Z}}_{\rm{0}}} - {Z_0}}}{{{Z_0} + {Z_0}}}=0\)

This indicates that all the power is transferred to the load and there is no reflected power, i.e. maximum power is transferred to the load.