Pi filter purpose on Lorawan reference design

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Hello everyone,
In the schematics en.MB1389-WL55JC-highband-E02_Schematic,
there's a Pi filter following the RF switch before it links to the SMA connector for the antenna.

Upon calculation, I found that the cutoff frequency of this low-pass pi filter is approximately 1800 MHz, which is significantly higher than the 870 MHz of LoraWAN. Could someone clarify the intention behind including this section in the schematics?
Ultimately, I intend to integrate a chip antenna onto the PCB and eliminate the SMA connector.
Should I retain these filters, or do I need to adjust the values of the pi filter components?
Thank you!

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STTwo-32Best answer

ST Technical Moderator

Hello @Levan

For such a specific use case, I suggest you submit a support ticket using our Online support platform or contact one of our FAEs.

Best Regards.

STTwo-32

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