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REPORT # 56050AF
9
2. RADIATED EMISSIONS FCC CFR 47 PART 15 SUBPART C
2.1 Radiated Emissions
2.1.1 Test Setup and Procedure
The EUT was placed on a wooden table 1 meter wide and 1.5 meters long which rests
on a flush mounted, steel-top turntable on the open area test site as shown below. The
top of the table is 80 cm above the ground plane. The turntable can be rotated 360
degrees. Measuring antenna is set at the prescribed distance. Measurements are made
with broadband antennas that have been correlated with tuned dipole antennas. The
mast is 4.5 meters high and is self-supporting. The height of the antenna can be varied
from 1 to 4 meters. Positioning of the antenna is controlled remotely.
on a flush mounted, steel-top turntable on the open area test site as shown below. The
top of the table is 80 cm above the ground plane. The turntable can be rotated 360
degrees. Measuring antenna is set at the prescribed distance. Measurements are made
with broadband antennas that have been correlated with tuned dipole antennas. The
mast is 4.5 meters high and is self-supporting. The height of the antenna can be varied
from 1 to 4 meters. Positioning of the antenna is controlled remotely.
Open Area Test Site
ADJUSTABLE
ANTENNA
HEIGHT
(30m) 1-6 Meters
(10m) 1-4 Meters
(3m) 1-4 Meters
ANTENNA
HEIGHT
(30m) 1-6 Meters
(10m) 1-4 Meters
(3m) 1-4 Meters
Flush Mounted
Rotating Turntable
Rotating Turntable
3, 10, 30 Meters distance as specified
Ground
Plane
Plane
EUT
REPORT # 56050AF
1 0
Radiated Test Setup and Procedure - contd.
The EUT is put into the operational test mode as stated in Section 1.4, it is then started.
The spectrum analyzer is setup to store the peak emission over the frequency range of
the antenna. Peak EUT and ambient emissions are stored while the turntable is rotated
360
0
. The Peak spectrum analyzer trace is then plotted with the addition of antenna and
cable correction factors. The limit is plotted on the same graph. A receiver with CISPR
Quasi Peak detector is then used on the frequencies identified as the highest with
respect to the plotted limit. Ambients are noted on the graph along with EUT emissions.
The highest emissions are maximized.
To maximize emissions levels, the turntable is rotated and the antenna is raised and
lowered to determine the point of maximum emanations. The cables are then
manipulated at that point to maximize emissions. Measurements are made with the
antennas in each horizontal and vertical polarization. The data obtained from these tests
is corrected with the proper cable, preamplifier and antenna factors. The results are then
transcribed onto tables that show the maximum emission levels. The highest emissions
are listed in a Radiated Emissions Summary table.
If no emissions can be found, the lowest harmonics of the EUT clocks within the bands
of the standard are tuned into with the receiver. If no emissions are found, the noise floor
will be entered to the table and noted. A minimum of six frequencies will be logged.
Summary results will reflect only actual emissions from the EUT.
Quasi Peak detector is then used on the frequencies identified as the highest with
respect to the plotted limit. Ambients are noted on the graph along with EUT emissions.
The highest emissions are maximized.
To maximize emissions levels, the turntable is rotated and the antenna is raised and
lowered to determine the point of maximum emanations. The cables are then
manipulated at that point to maximize emissions. Measurements are made with the
antennas in each horizontal and vertical polarization. The data obtained from these tests
is corrected with the proper cable, preamplifier and antenna factors. The results are then
transcribed onto tables that show the maximum emission levels. The highest emissions
are listed in a Radiated Emissions Summary table.
If no emissions can be found, the lowest harmonics of the EUT clocks within the bands
of the standard are tuned into with the receiver. If no emissions are found, the noise floor
will be entered to the table and noted. A minimum of six frequencies will be logged.
Summary results will reflect only actual emissions from the EUT.
The field intensity measurements are made using standard techniques with a spectrum
analyzer or EMI receiver as the calibrated Field Intensity Meter (FIM). Preamplifiers and
filters are used when required.
analyzer or EMI receiver as the calibrated Field Intensity Meter (FIM). Preamplifiers and
filters are used when required.
When using the Hewlett Packard 8566B Spectrum Analyzer as the FIM, the Analyzer is
calibrated to read signal level in dBm. Where:
calibrated to read signal level in dBm. Where:
0 dBm (50 ohms) = 107 dBµV (50 ohms)
The signal level (dBµV) = indicated signal level (dBm) + 107 dB. To obtain the signal
level in dBuV/m it is necessary to add the antenna factor in dB.
level in dBuV/m it is necessary to add the antenna factor in dB.
Example of Typical Calculation
Measurement Distance = 3 Meter
Measurement Distance = 3 Meter
Rohde and Schwarz reading @ 60 MHz
49.0 dBµV
Antenna Factor
+7.5 dB
Cable Loss
+2.0 dB
Preamplifier
-25.5 dB
Total Factors
-16.0 dB/m
Field Strength dBµV/m at 3 Meter =
33.0 dBµV/m
REPORT # 56050AF
1 1
2.2 Radiated Emissions Compliance Data
The EUT was compliant with CFR 47 Part 15 Subpart C 15.231 (a)
Fundamental Frequency Measurements and Spurious Emission Measurements
Per CFR 47 part 15 at 3 meters
Fundamental Frequency Test Data
Griffin Technology
EUT: AirClick
Amp
Cable Antenna
Total
Polarity
Freq
Meas'd Factors Factors Factors
Factors
Total
Limit
Delta
Azimuth Height
Hor
(MHz)
(dBuV)
(dB)
(dB)
(dB)
(dBuV/m) (dBuV/m) (dBuV/m)
(dB)
(degree)
(m)
Vert
434.01
67.60
26.50
4.50
18.10
-3.90
63.70
80.80
-17.10
88
1.00
Vert
QP
434.01
64.50
26.50
4.50
18.30
-3.70
60.80
80.80
-20.00
21
3.79
Hor/
QP
Meas.
Type
Ave,
QP, PK
Spurious Radiated Emissions Test Data
Griffin Technology
EUT: AirClick
Amp
Cable Antenna
Total
Polarity
Freq
Meas'd Factors Factors Factors
Factors
Total
Limit
Delta
Azimuth Height
Hor
(MHz)
(dBuV)
(dB)
(dB)
(dB)
(dBuV/m) (dBuV/m) (dBuV/m)
(dB)
(degree)
(m)
Vert
867.99
51.40
27.00
6.50
25.20
4.70
56.10
60.80
-4.70
170
1.96
Hor/
QP
867.99
48.20
27.00
6.50
24.20
3.70
51.90
60.80
-8.90
205
1.00
Vert
QP
Meas.
Type
Ave,
QP, PK
Spurious Radiated Emissions Above 1 GHz Test Data
Griffin Technology
EUT: AirClick
Duty Corrected
Amp
Cable Antenna
Total
Polarity
Freq
Meas'd Cycle
Meas'd
Factors Factors Factors
Factors
Total
Limit
Delta
Azimuth Height
Hor
(MHz)
(dBuV)
(%)
(dBuv)
(dB)
(dB)
(dB)
(dBuV/m) (dBuV/m) (dBuV/m)
(dB)
(degree)
(m)
Vert
1301.88
67.60
70%
47.32
24.22
2.68
25.39
3.85
51.17
60.80
-9.63
14
1
Vert
Peak
1735.94
60.10
70%
42.07
26.26
3.13
27.66
4.53
46.60
60.80
-14.20
192
1
Vert
Peak
1301.83
59.25
70%
41.48
24.22
2.68
25.49
3.95
45.42
60.80
-15.38
78
2.34
Hor
Peak
1735.82
52.85
70%
37.00
26.26
3.13
27.71
4.58
41.57
60.80
-19.23
76
1.52
Hor
Peak
2169.84
41.20
70%
28.84
26.51
3.61
29.74
6.85
35.69
60.80
-25.11
255
1
Vert
Peak
Meas.
Type
Ave, PK
•
Highest frequencies relative to the Limit.
REPORT # 56050AF
1 2
2.3 Duty Cycle Calculations
Duty Cycle = PW X (Number of Pulses) / Period
Duty Cycle = 70 ms * 10 (700 ms) / 1000 ms. = 70%
Duty Cycle = 70 ms * 10 (700 ms) / 1000 ms. = 70%
2.4 Climatic Conditions
The climatic conditions during the Radiated Emissions tests were recorded as follows:
Measured Value
Acceptable
Ambient Temperature
13 C
15 to 35° C
Relative Humidity
40%
25 to 75%
2.5 Compliant Statement
The EUT was compliant with Part 15 Subpart C
YES
NO
CA
CA Test Engineer’s Initials
PW = 70ms
Period
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