Quanta Computer HFSWM100, Отчет испытаний ЭМИ

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ETC Report No. : ET90S-11-032 Sheet 8 of 104 Sheets
FCC ID. : HFSWM100
Rev. No 1.0
4 RADIATED EMISSION MEASUREMENT
4.1 Applicable Standard
For unintentional radiator, the radiated emission shall comply with 15.109(a).
For intentional radiators, according to 15.247 (a), operation under this provision is limited
to frequency hopping and direct sequence spread spectrum, and the out band emission shall
be comply with 15.247 (c)
4.2 Measurement Procedure
1. Setup the configuration per figure 1 and 2 for frequencies measured below and above 1
GHz respectively.
2. For emission frequencies measured below 1 GHz, it is performed in a semi-anechoic
chamber to determine the accurate frequencies of higher emissions. For emission
frequencies measured above 1 GHz, a pre-scan be performed with a 1 meter measuring
distance before final test.
3. For emission frequencies measured below and above 1 GHz, set the spectrum analyzer on
a 100 kHz and 1 MHz resolution bandwidth respectively for each frequency measured in
step 2.
4. The search antenna is to be raised and lowered over a range from 1 to 4 meters in
horizontally polarized orientation. Position the highness when the highest value is
indicated on spectrum analyzer, then change the orientation of EUT on test table over a
range from 0 to 360with a speed as slow as possible, and keep the azimuth that highest
emission is indicated on the spectrum analyzer. Vary the antenna position again and
record the highest value as a final reading. A RF test receiver is also used to confirm
emissions measured.
Note : A band pass filter was used to avoid pre-amplifier saturated when measure TX
operation mode in frequency band above 1 GHz.
5. Repeat step 4 until all frequencies need to be measured were complete.
6. Repeat step 5 with search antenna in vertical polarized orientations.
7. Check the three frequencies of highest emission with varying the datarate, placement of
ANT. cables associated with EUT and changed ANT.1 ~ANT.4 to obtain the worse case
and record the result.