User's Manual

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HW Design Guidelines
Figure 16. RF pad layout suggestion
Figure 17. RF matching guide
3.2. Interference and sensitivity
This section includes tips to assist developers in identifying the interference that may affect
M18QF/M18QA Series modules when used in systems.
Interference from other wireless devices
Harmonics, inter-modulated signal generated from wireless devices that
fall in RX ranges of the modules, may result in degraded RX performance.
It is highly recommended to check RX performance of entire systems
within the shielding environment.
Interference from host interface
High-speed signal-switching elements in systems can easily couple noise
into the module (Ex.: DDR memory, LCD modules, DC-DC converter, PCM
signal).
Methods to avoid sources of interference
Antenna location is important; we recommend directing the antenna