- Windscreen Antennas
Windscreen antenna integrated in concept vehicleRadiation pattern and currentdistribution of windscreen antenna
The proliferation of communication devices that are required in modern automobiles, require manufacturers to include more and more antennas into vehicles. Requirements include FM/AM antennas, TV antennas, etc. Ideally, antennas should be integrated in unobtrusive ways.
A prominent modern development is to include antennas into the windscreens of a vehicle. These windscreens include multiple layers of glass and wiring that form the antenna. As with other antenna designs, engineers require the ability to simulate new designs to evaluate many antenna operating characteristics, such as efficiency, impedance bandwidth and far-field radiation pattern.
To address this need, FEKO includes a solution method based on the MoM that can be used for rigorous analysis of windscreen antennas. The method meshes only the metallic antenna elements, so the resource requirements that are devoted to modelling of the dielectric layers of the glass is almost negligible. Features of the method include:
- Boundaries of the dielectric interfaces between different layers of glass are accurately taken into account
- Coupling between closely spaced antenna elements are taken into account
- Finite size glass antennas can be integrated into a full car model
- Curvature and rotation of the window is considered
FEKO also provides the user with innovative tools for the specification of windscreen antenna CAD, e.g. the constrained surface tool that creates a windscreen work surface. This work surface is in effect a 2D plane where windscreen antennas can easily be specified, while the work surface takes care of the mapping of the antenna to 3D space, conformal to the surface of the windscreen antenna. (Users can watch an instructional video on the windscreen antenna tool in the Help Centre)
In the example below, a FEKO model of a car with integrated windscreen antenna is shown with a comparison of simulated and measured reflection coefficient data. These results show that FEKO can predict the performance of such antennas very accurately.
Detail model of windscreen antenna Windscreen antenna reflection coefficient