Specifications

EMC-CS-2009.1
© Copyright Ford Motor Company – All Rights Reserved Page 40 of 121
February 11, 2010
For both procedures, field characterization shall be performed at the Level 2 field strengths listed in Table 11-3. Field
characterization at lower field strengths with subsequent power scaling for higher field strengths is not permitted.
When performing testing in Bands 6 and 7, the forward power required to achieve the field strengths listed in Table
11-3 is greatly influenced by the transmit horn antenna selected. The antenna near field gain compression
characteristics can significantly impact the actual power needed to achieve the required field strengths at 1 meter.
Given this issue, selection of the antenna should not be based simply on the published antenna gain. Also, the high
power levels needed to achieve the desired field strength have been shown to significantly impact the VSWR of some
antennas. A list of recommended antennas may be found at http://www.fordemc.com
.
a) When performing testing in Bands 6 and 7 using pulse modulation, CW shall not be used for leveling prior to
application of pulsed modulation.
b) Use the step frequencies listed in Table 11-2. Use the modulation as specified in Table 11-3.
d) All modulation dwell time (i.e., time that RF is applied for per modulation type) shall be at least 2 sec.
e) The test shall be performed using both horizontal and vertical antenna polarization.
f) At test frequencies ≥ 1000 MHz, the DUT shall be tested in a minimum of three (3) orthogonal orientations unless
otherwise stated in the EMC test plan.
g) If deviations are observed, the field shall be reduced until the DUT functions normally. The field shall then be
increased until the deviation occurs. This level shall be reported as deviation threshold.
11.5.2.2 Reverberation Method
a) Use test frequencies according to Table 11-2. Use the modulation specified in Table 11-3 except for bands 6 and 7.
For bands 6 and 7, increase the pulse duration (PD) to 6 usec.
b) All modulation dwell time (i.e., time that RF is applied for per modulation type) shall be at least 2 s.
c) Electric field probes shall not be used during the test.
d) The test chamber shall be calibrated according to Annex C section C.1.1 (Field Uniformity Validation)
e) Prior to collecting data, the procedures of Annex C, section C.2 (Calibration and DUT loading check) shall be
performed.
f) The transmit antenna shall be in the same location as used for calibration according to Annex C.
g) The DUT shall be exposed to each field level and frequency at each mode tuner position.
h) The chamber input power for the electric field levels is determined via the equation:
()
2
924
_
__
⎥
⎥
⎥
⎥
⎦
⎤
⎢
⎢
⎢
⎢
⎣
⎡
⋅
=
fCLFE
E
PowerInputTest
or
test
where:
E
test
= Required field strength in V/m (see Table 11-3)
CLF(f) = Chamber loading factor from Annex C, section C2, step g).
924or
E
t
= Normalized electric field from the empty chamber calibration from Annex C, section C.1. It may be
necessary to linearly interpolate (CLF and normalized electric field values) between the calibration frequency
points.
i) If deviations are observed, the field shall be reduced until the DUT functions normally. Then the field shall be
increased until the deviation occurs. This level shall be reported as deviation threshold.