How do I know that a Dual-Band USB WiFi dongle will work on Raspbian or other Linux distrobution?

Question

How do I know if a Dual band USB WiFi dongle will work on a Raspberry Pi running Linux? I know that Linux must have a driver that supports the wifi chipset used in the dongle. But with the number of WiFi dongles available how do you choose?

Answer 1

You can find a detailed list of supported RPi USB Wi-Fi Adapters.

If you have the USB/WiFi dongle available you can look at its valid interface combinations with iw list. For example on a RPi 4B you will find:

--- snip ---
valid interface combinations:
     * #{ managed } <= 1, #{ P2P-device } <= 1, #{ P2P-client, P2P-GO } <= 1,
       total <= 3, #channels <= 2
     * #{ managed } <= 1, #{ AP } <= 1, #{ P2P-client } <= 1, #{ P2P-device } <= 1,
       total <= 4, #channels <= 1
--- snip ---

Here you will find how much channels are supported by a particular interface combination. For a more detailed discussion of this issue you can look at Can RPi4 run simultaneously on dual band (WiFi 2.4GHz / 5GHz)?.

Answer 2

You can check on wiki.kernel.org for supported Drivers and his supported PHY modes : A/B/G/N/AC

• 802.11 B/G work on 2.4GHz Band and 802.11 A/AC work on 5Ghz Band so it's Dual Band.

• 802.11 N have : single-band 2.4 GHz equipment (the oldest), dual-band adapters (2.4 GHz or 5 GHz) or dual-radio: 2.4 GHz and 5 GHz simultaneously.

I'm confuse with 802.11n for my answer. But I think if 802.11n is in the supported PHY modes, 2.4GHz and 5GHz Bands should be supported by the driver.