Bluetooth Audio Module
Figure 20: Antenna reference design
9.2
Matching network in free space
The specs of a Fractus standard antenna are measured in their evaluation board (in free space),
which is an ideal case. In a real design, components nearby the antenna, semiconductors,
LCD’s, batteries, covers, connectors, etc affect the antenna performance. This is the reason
why it is highly recommended to place 0402 pads for a PI matching network as close as
possible to the antenna feeding point. Do it in the ground plane area, not in the clearance area.
This is a degree of freedom to tune the antenna once the design is finished and taking into
account all elements of the system (batteries, displays, covers, etc).
Figure 21: PI match network example
Shanghai Ehong Technologies Inc
Summary of Contents for EH-MB05
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