The antennas on this page do not require a ground plane, but adding one will typically improve performance if your installation will allow it. Ground planes are metal sheets of metal (typically aluminum or galvanized steel) that the antenna mounts on top of. For optimal performance a ground plane of a minimum of 16" in diameter is typically recommended. The ground plane does not need to be grounded or wired to the chassis ground of the vehicle, the metal sheet simply helps the cellular and WiFi signals bounce into the antenna optimizing performance. Ground planes are available in various sizes on our store including a flexible adhesive ground plane or a 16 inch aluminum ground plane. For more information on ground planes visit the Ground Plane Guide on Mobile Internet Resource Center.
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