Never thought I'd be interested in the isolation in this direction (instead of LO to RF)... but here's my reasoning:
I am using the ADL5801 in a radar receiver where the path length for the LO signal is unfortunately quite long.
I get some ghost returns which seem to coincide with the following path:
--> In at RF port of ADL5801
--> Out at LO port of ADL5801
--> along LO path to remote coupler (where LO signal originates)
--> reflect at the coupler port
--> return to mixer LO port
--> get mixed with original LO signal to form a ghost return
Is there anyone else who thinks this is plausible ?
What would the isolation typically be from the RF port to the LO port of a device like this?