Overview of DFS - Dynamic-Frequency-Selection/Overview-of-DFS

Dynamic Frequency Selection (DFS) is an interference mitigation technique that allows devices operating in unlicensed 5GHz frequency to share the spectrum and co-exist with civilian and military radar systems. DFS is supported by the IEEE 802.11h wireless local area network standard and is mandated in certain regulatory bands for radar avoidance.

The following table highlights different 5GHz frequency bands, in which DFS operation is mandatory. The DFS regulatory restrictions can differ between countries or regions.

Radar devices typically operate in a range of frequencies known as DFS channels (UNII-2A and UNII-2C). The list of DFS channels varies based on global regulatory domains.