Additional LC on RF pin in ESP32-S3 reference schematic

[jaydeepd]

Hi,

I am designing a board with ESP32-S3 SoC. While reviewing the ESP32-S3 Hardware Design Guidelines document, I noticed that in the RF section, the reference schematic shows additional LC components after the Pi network.

I have not seen an inductor and capacitor in series with each other connected between the RF and Ground pin in any similar RF designs. For example, I have designed a board using ESP32-S2, but the ESP32-S2 Hardware Design Guidelines only contain a Pi network on the RF pin.

I am looking for reasons to use an LC structure on the RF pin. Is it to suppress harmonics and to pass FCC/CE radiation tests?
If the board needs to be FCC certified, will including the LC structure help it pass radiation tests, or can it be safely omitted?

Thanks.