This document discusses car antennas and the potential for transparent antennas. It begins by outlining common car antenna types and frequency spectrums used. Requirements for car antennas include aesthetics, manufacturability, durability and more. Transparent conductors that could enable transparent antennas, like indium tin oxide, are then examined. Finally, the document explores using grid antenna designs made of transparent conductors as an alternative to traditional antennas, though transparency would lower their radio frequency performance.
15. Implemented Antenna for DSRC
Omnidirectional Microstrip Array
0o
0 dB
-30o
30o
Measured
Simulated
-10
-60o
60o
-20
-30
-90o
90o
-30
-20
-120o
120o
-10
-150
o
0 dB
180
15
o
150o
16. We defined new requirements
•
Higher Gain
•
•
Beam Control
Reduced Impact
to the driver view
Directive transparent Antennas
Beamforming network
System integration
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Array
Beamforming Networks
Transparent Antenna
18. Transparent Conductors
Transparent
Conductor
Characteristic
Indium Tin
Oxide (ITO)
Most commonly used, durable, chemical resistance
to moisture, can be precisely etched
Indium Zinc Oxide
(IZO)
Is used quite often in the LCD’s, easily etchable,
but not as durable as ITO
Zinc Oxide with
Aluminum (AZO)
Lower cost and relatively good optical transmission,
lower chemical resistance to moisture
Fluorine doped Tin
Oxide (FTO)
Difficult to etch fine patterns has made its use
primarily for plasma displays
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19. Transparent Conductors (common application)
Advantages
Low production cost
High resistance to dust and water
Best used with a finger, gloved or stylus
Best suited for handwriting recognition
Advantages
Looks brighter and sharper
Highly touch sensitivity
Supports multi-touch
Disadvantages
Disadvantages
Not too sensitive
Poor contrast
Does not support multi-touch
Not working with simple gloves
More expensive
Glass is more prone to breaking
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24. Conclusions
• Transparent antennas can be a solution for car antennas
• ITO based antennas can be a solution, however with
poor RF performance
• Grid antennas are a valid alternative
• Transparency is inversely proportional to antenna
efficiency
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