User manual

Test Report ------------------------------------------------------------------------------- 45/48
Report No.: M47ET060805 (ETSI EN 301 489)
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Chapter 13 Radiated Emission Test
Test condition and setup
Pretest:
Prior to the final test (OATS test), the EUT is placed in a shielded enclosure, and scan from
30MHz to 1GHz. This is done to ensure the radiation is exactly emitted from the EUT.
Final test:
Final radiation measurements are made on a 10 – meter, open-field test site. The EUT is
placed on a nonconductive table, which is 0.8m height, the top surface is 1.0 x 1.5 meter. The
entire placement is according to EN 55022.
The whole range antenna is used to measure frequency from 30 MHz to 1GHz. The final
test is used the spectrum analyzer (EMI Receiver). Measure more than six top marked
frequencies generated form pretest by computer step by step at each frequency.
The EUT is rotated 360 degrees, and antenna is raised and lowered from 1 to 4 meters to
find the maximum emission levels. The antenna is used with both horizontal and vertical
polarization.
Appropriated preamplifier which is made by TRC is used for improving sensitivity and
precautions is taken to avoid overloading .The spectrum analyzer’s 6dB bandwidth is set to 120
kHz, and the EUT is measured at quasi-peak (below 1GHz) mode.
If the emission is close to the frequency band of ambient, the tester will recheck the data
and the corrected data will be written in the test data sheet. If the emission is just within the
ambient, the data from shielded room will be taken as the final data.