Conducted RF Test
The source of disturbance covered by this test is basically an
electromagnetic field, coming from intended RF transmitters, that may act on the whole
length of cables connected to an installed equipment. The dimensions of the disturbed
equipment, mostly a sub-part of a larger system, are assumed to be small compared with the
wavelengths involved. The in-going and out-going leads: e.g. mains, communication lines,
interface cables, behave as passive receiving antenna networks because they can be several
wavelengths long.
Between those cable networks, the susceptible equipment is exposed to currents flowing
"through" the equipment. Cable systems connected to an equipment are assumed to
be in resonant mode (l /4, l /2 open
or folded dipoles) and as such are represented by coupling and decoupling devices having
common-mode impedance or 150W with respect to a ground
reference plane.
This test subjects the EUT to a source of disturbance comprising electric and magnetic
fields, simulating those coming from intentional RF transmitters. These disturbing fields
(E and H) are approximated by the electric and magnetic near-fields resulting from the
voltages and currents caused by the test set-up.
The EUT is subjected to an electromotive force (e.m.f.) of 3 V or 10 V from 150 kHz to
80 MHz. This frequency range is 80% amplitude modulated with a 1 kHz sine wave. The signal
generator provides the modulated frequency at a step rate of 1% of fundamental to the RF
amplifier. The dwell time at each frequency is not less than the time necessary for the
EUT to be exercised, and able to respond. Clamp injection on all cables of the EUT is used
to couple the e.m.f. to the EUT.
No tests are required for induced disturbances caused by electromagnetic fields coming
from intentional RF transmitters in the frequency range 9 kHz to 150 kHz.
