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Old 10-10-2017, 09:26 PM
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dtvmcdonald dtvmcdonald is offline
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Join Date: Nov 2012
Posts: 1,191
The big problem with I-Q demod is that to get it really right required two
delay lines, one for Y, one for I. And to get them right and the filters with good phase response is not easy ... without digital (or bucket brigades).

My personal opinion is that best is to use any two axes and get the response
quite flat to about 700-800 kHz then rolling off to zero at 1.5 MHz. on both
axes. Few folks notice the resulting bleedthrough from I into Q. Using
equal bandwidths the results are identical independent of the axes used.

However, other people may seriously object to the bleedthrough.
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