EMI Suppression Filters (EMC and Noise Suppression)Noise Suppression Measures for Wi-Fi 6 (2)

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Wi-Fi 6 is compatible with the 2.4 GHz band and 5 GHz band, but when noise (DC-DC converter switching noise, etc.) in the 0.1 GHz to 1 GHz range is applied to the front end of the 2.4 GHz band, third-order intermodulation distortion that interferes with the 5 GHz band occurs.
Communication disturbances occur if this is transmitted to the front end of the 5 GHz band through power lines, etc.
If using a base unit, communication with devices that use a 2.4 GHz band Wi-Fi may be the reason. For wireless units, simultaneous use with Bluetooth® may be the reason.

A noise filter that supports the 5 GHz band is applied to prevent noise entry in the 5 GHz band. The BLF03VK is a noise filter that was designed for effective removal of noise in the 5 GHz band.
Inserting the BLF03VK series into the power line can prevent third-order intermodulation distortion from flowing into the front end of the 5 GHz band.

Equipping high speed interfaces can also lead to reception sensitivity deterioration.
As Wi-Fi communication becomes faster, the speed of internal data transmission interfaces will also increase, and frequencies that will interfere with Wi-Fi signals will also be processed.
For this reason, PCI Express signals are radiated and the 2.4 GHz band Wi-Fi reception sensitivity deteriorates.
Also, due to the popularity of USB Type-C connectors, support for USB 3.1 has progressed, and due to the USB 3.1 having a signal frequency close to the 2.4 GHz band, there are examples that lead to Wi-Fi reception sensitivity deterioration.

A noise filter is to be inserted on the interface signal line to eliminate noise that interferes with Wi-Fi from high speed interfaces.
However, since these interfaces use high speed signals, you are required to select those that do not affect signal waveforms.
In principle, common mode choke coils/common mode noise filters (CMCC) do not affect differential signals, but since there are differential mode impedances in actual products to some extent, you are required to select applicable parts.

⇒Measures can be taken by inserting the BLF03VK series to the power line

⇒Measures can be taken by using common mode choke coils/common mode noise filters that support high speed signals on the high speed interface signal line