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Method of matching

When matching is performed in a transmission linę context it is done in the way illustrated

in Figurę 3.1. In this figurę two matching systems are illustrated. The matching system on the right is intended to transform the load impedance Zlso that it becomes equal to the characteristic impedance Zo of the transmission linę. When that is done the input impedance of the transmission linę with its transformed load is simply equal toZo. The matching system on the left has the function of transforming the characteristic

impedance of the transmission linę Zo further to become the complex conjugate of the

source impedance Zs. In both cases the matching systems consist of purely reactive elements so no power is lost within them.lt may be shown, but we will not do so here, that the same matching system will

transform the source impedance Zs into the real impedance Zo, so that from either of two possible points of view maximum power transfer occurs between the source and the

input end of the transmission linę.

The matching systems often consist of short lengths of transmission linę with reactive elements connected in series or in parallel.