NARDA PMM AS02, User Manual, Page: 49 / 56

Radiated Emission and Immunity testing 3-1
3 - Radiated Emission and
Immunity testing
3.1 Radiated Emission
testing
The electromagnetic emissions emanating from the equipment under test
(EUT) are measured during a radiated emission test
According to the international Standards, the purpose of this test is to verify
that the EUT's emissions are below specified limits during operation.
The receiving antenna middle point can be located either at 3 or 10 meter
from the EUT and must scan from 1 to 4 meters in height. This scanning
helps the operator to locate the EUT's worst case electromagnetic
emission level.
The typical emissions test set-up is composed of:
•
receive antenna;
•
interconnecting cable;
• preamplifier;
•
preamplifier cable;
• meter receiver.
3.1.1 The Antenna Factor
The performance of the antenna relating to the value of the incident’s field
to the voltage output of the antenna is the Antenna Factor; this value is
provided in dB/m by the manufacturer.
3.1.2 The
interconnecting
cable
The cable connects the antenna to the preamplifier or meter receiver input.
There is a loss in the cable resulting in a reduction of the measured signal,
to increase the measure accuracy, these losses need to be added to the
measured value.
3.1.3 The preamplifier If the Receiver or the Spectrum Analyzer have a high input noise figure,
may be necessary to compensate it with a preamplifier installed between
the antenna and the meter receiver. The preamplifier makes the measured
signal larger, thus the gain of the preamplifier must be subtracted from the
measured value to obtain the correct final result.
3.1.4 The preamplifier
interconnecting
cable
An additional cable to connect the preamplifier to the meter receiver input
may be necessary if the preamplifier is installed.
There is a loss in the cable resulting in a reduction of the measured signal,
to increase the measure accuracy, these losses need to be added to the
measured value.
Document ASEN-81109 -

NARDA 2018