Impedance Matching
If a source and load are both resistive (i.e. Z1 and Z2 have zero or very small imaginary part) then a resistive L pad can be used to match them to each other. As shown, either side of the L pad can be the source or load, but the Z1 side must be the side with the higher impedance.
There is an inherent insertion loss
where = power dissipated by load and = power dissipated by the pad resisters. Large positive numbers means loss is large.
The loss is a monotonic function to the impedance ratio. Higher ratios require higher loss.
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