Impedance matching vs max power transfer criterion

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Si14
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Hello,

I wonder if there's any difference between the "impedance matching" and "maximum power transfer" criterion?
I assume in both cases, one impedance should be designed to be the complex conjugate of the other.

Thanks.
 
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By PERFORMING impedance matching you can maximize power transfer.

Wiki says,

...impedance matching is the practice of designing...

http://en.wikipedia.org/wiki/Impedance_matching"
 
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Si14 said:
I wonder if there's any difference between the "impedance matching" and "maximum power transfer" criterion?
I assume in both cases, one impedance should be designed to be the complex conjugate of the other.
Why don't you sketch up a simple circuit with a source that has an internal impedance of your choice, and see how various load impedances affect the power transfer?
 
A quarter-wave transformer (quarter wavelength of transmission line) between the source and the load can maximize power transmission by mismatching the load to the coax. See

http://en.wikipedia.org/wiki/Quarter_wave_impedance_transformer

For example, a quarter wave of 50-ohm transmission line can match a 100-ohm source to a 25-ohm load.

Bob S