Which frequency is commonly used by WiFi networks in the 2.4 GHz band?

• A. 2.2 GHz
• B. 3 GHz
• C. 3.5 GHz
• D. 2.4 GHz

Answer: (D)

The frequency commonly used for WiFi in the 2.4 GHz band is 2.4 GHz. This part of the spectrum is an unlicensed ISM band, which is why WiFi devices can operate there without individual licenses and why many devices worldwide support it. The 2.4 GHz signal travels well through walls and over longer distances, giving good range, but it shares the spectrum with many other devices (like Bluetooth, microwaves, and cordless phones), so interference can be higher and peak speeds can be lower than on the higher 5 GHz band. In practice, WiFi uses several 2.4 GHz channels, with non-overlapping options like channels that minimize overlap to reduce interference. The other frequencies listed aren’t standard for the 2.4 GHz WiFi band, as they fall in different parts of the spectrum used for other services.