2. Electromagnetic Compatibility
ability of an electronic system to function
The
properly in its intended electromagnetic
environment.
IR Reflecting
Conductive
Windshield
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3. IR Reflecting vs. IR Absorbing
IR Heat Absorbing
Green glass – higher iron levels
Absorbs the sun’s heat becoming hot to the
touch
Reradiates heat inside of vehicle
IR Heat Reflecting
Conductive metallic coating
Sheet Resistance of less than 3ohms/sqr
Glass reflects the sun’s heat staying cool
in EU, up to 30%
Common
be mandated by CA – CARB
May
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8. Deletion
Areas covered by black paint.
Mask or delete
Deletion line should be one continuous line to aid manufacturability.
Keep black band as wide as possible.
Include a third visor black paint area. Third Visor
Mask/Deletion Line
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9. Frequency Selective Surfaces (FSS)
The door of a microwave oven
blocks microwave while
allowing visible light to pass.
Band Pass
Band Stop Black = Metal
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20. Frequency Selective Surfaces
Provide Laser etched or completely deleted areas for devices mounted on or in close
proximity to the windshield.
LASER
Treated
Areas (3)
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21. Deletion Methods
Masking and Abrasive Wheel
Periphery
band
Black
Visor
Third
Toll
LASER
patterning
Fine
Frequency Selective Surfaces
RF
of antennas
De-coupling
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22. DESIGN GUIDLINES
Alternate Locations:
Consider mounting antennas in other areas.
Roof or Trunk
GPS, Cell, Satilite Radio
Package shelf
RKE, Tire Pressure
Rear window
Screen print Silver
dash/IP mount devices (GPS) as close as possible to
Keep
the bottom front of the windshield
maximize the field of view and
minimize the size of deletion needed.
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23. DESIGN GUIDLINES
Are specifications based upon function or specific device?
Specifications are often based upon the capability of a specific antenna rather than what is
actually needed for reliable operation.
An OEM GPS specification calls for either 28dB or 22dB of gain depending upon location: on the
roof or in the dash. Which location must meet the 28dB spec.?
Answer: the roof!
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24. Conclusions
IR reflecting glazing can improve mileage, lower
emissions and increase comfort.
Usage is increasing and may be mandated.
Effective engineered solutions are available to
address compatibility issues.
in millions of vehicles.
Deployed
on some high end vehicles.
Standard
S-Class in all positions since 2000
Mercedes
Complex electronic systems
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