How to design an antenna on a PCB

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Doc ID 15629 Rev 6

Figure 16 shows an example of a not recommended implementation. The electromagnetic

flux is greatly attenuated by the short-circuited loop surrounding the M24LRxx antenna.

Figure 16. Not recommended implementation

Figure 17 shows an acceptable implementation, if the antenna and the ground plane do not

overlap.

Figure 17. Acceptable implementation

Figure 13 remains the best solution.

STMicroelectronics recommends designers to allocate a dedicated area of the PCB layout

to the antenna only, with no surrounding ground layer.

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