There is an Agilent app note about this... The short answer is: near z0 of
your couplers, ( 50 ohms) use a network analyzer, at high or low
impedances, use voltage and current.
regards,
Cliff


"dansawyeror" wrote in message
...
All,

What is the best way to base impedance measurements, by voltage and
current phase or by forward and reflected power?

First I assume both methods provide the data to measure impedance.

It would seem that both suffer from the real effects of the taking the
measurement. Measuring voltage suffers from the effects of the reflected
signal, I would assume current does as well. Couplers have a built in
cross talk parameter.

Thanks,

- Dan