Hi All,
I was hoping someone could help me
with a fundamental issue.
I have had some
EMC problems (radiated) and am trying to analyse
the results.
The test is done by monitoring
the radiated signal with an antenna placed 1m from
the DUT. The levels are then given in dBuV/m.
I understand that this is a measure of the Electric
field strength, but my question is how to relate
this to an absolute power measurement.
Is it
a straight conversion from dBuV to dBm, assuming
a 50 ohm system, and can the /m part of the unit
be dropped because of the distance between DUT and
antenna being 1m?
If this reasoning was followed,
a +30dBuV/m translates to -77dBm/m, or -7dBm power
level at source if a cable with 70dB isolation was
used. (cable connected to known source of offending
signal and terminated into 50 ohm)
Am I way
off the mark, and if so can someone please shed
some light?