Installation and Manual Documentation
Document date:
CC-DA/ESR1
CR5CPCCF
18 Feb 2020
Page:
17
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and passing on rights, with us. The valid issue of this template is filed in CC-DA process landscape.
Classification of reflection caused by the fascia
1.
Reflection coefficient <-10 dB
is achieved when fascia has optimized thickness within a tolerance of ±0.2 mm and permittivity
within a tolerance ±0.02. Dielectric loss factor tanδ shall be <0.03.
2.
Reflection coefficient <-6 dB
is achieved when fascia has optimized thickness within a tolerance of ±0.2 mm and permittivity
within a tolerance of ±0.2. Dielectric loss factor tanδ shall be <0.05. This is the case for painted
bumper especially when various colors are used.
3.
Reflection coefficient >-6 dB
is achieved when fascia has no optimized thickness or a painting with high metallic content is used.
The attenuation may exceed the maximum allowed limit.
The examples described in the classification of reflection are derived from evaluation of flat plates
with constant thickness and homogeneous material. Deviations from this situation may cause a
change in classification and the vertical tilt angle of fascia has to be increased.
Surface Properties of the fascia
The surfaces of the fascia shall not exceed an average roughness height of 20 µm (corresponding
to ISO 1302 class N10; VDI 3400 class 45).
