Data Sheet

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3.4 Antenna Specification
Multiple antenna interfaces have been integrated on the REX3B module. As shown below
3.4.1 PCB Antenna
Figure 4-1. PCB Antenna
When using the PCB antenna output, note the following points:
1. Avoid placing the module inside a metal enclosure.
2. Avoid placing metal objects close to the PCB antenna (at least 1cm away, it is recommended
to be 2.7cm or more).
3. Do not place the module next to devices emitting electromagnetic radiation, such as
transformers.
The user circuit board should be designed to prevent its components, traces, or floors from
interfering with the PCB antenna of the wireless module. The basic principle is:
 Do not trace, lay or place other components around the PCB antenna
 PCBThe PCB antenna preferably protrudes from the PCB board
 Do not use metal housing around PCB antenna
Figure 4-2. PCB layout diagram for module antenna position selection
Can place components,
route, copper
Can not place
components, can not be
wired, can not be copper.
It is best to hollow
PCB Antenna