
6.3 Effect of Plastic and Metal Materials
The antenna on the BGM11S. is insensitive to the effects of nearby plastic and other materials with low dielectric constant and no sepa-
ration between the BGM11S. and plastic or other materials is needed. Also the board thickness doesn’t have any impact the module.
Any metal within the antenna area or in close proximity to the antenna area may detune the antenna. In this case it is possible to retune
the antenna by adjusting the width of the antenna loop. To avoid detuning of the antenna the minimum distance to any metal should be
more than 3mm. Encapsulating the module inside metal casing will prevent the radiation of the antenna.
Following picture shows how it is possible to adjust the frequency of the antenna. The antenna is extremely robust against any objects
in close proximity or in direct touch with the antenna and it is recommended not to adjust the dimensions of the antenna area unless it is
clear that a metal object, such as a coin cell battery, within the antenna area is detuning the antenna.
Figure 6.5. Tuning the antenna by adjusting the width of the antenna loop
6.4 Effect of Human Body
Placing the module in touch or very close to the human body will negatively impact antenna efficiency and reduce range.
BGM11S Blue Gecko
Bluetooth
®
SiP Module Data Sheet
Layout Guidelines
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