Some portions of the 5 GHz WLAN band is used by Radar, Weather satellites and other sensitive applications. The regulatory authorities of different countries determine on how transmission is to be attempted on these channel by WLAN devices. If transmission of any sensitive application is detected, the WLAN device should not attempt further transmission on that channel and move to a different channel of operation.
The DFS range is shown provided below.
The Table with centre frequencies are shown below
| Channel number | Frequency |
| 52 | 5260 |
| 56 | 5280 |
| 60 | 5300 |
| 64 | 5320 |
| 100 | 5500 |
| 104 | 5520 |
| 108 | 5540 |
| 112 | 5560 |
| 116 | 5580 |
| 120 | 5600 |
| 124 | 5620 |
| 128 | 5640 |
| 132 | 5660 |
| 136 | 5680 |
| 140 | 5700 |
802.11 DFS service provides the following (as is from the 802.11-2012 standard)
- Association of STAs with an AP in a BSS based on the STAs’ supported channels.
- Quieting the current channel so it can be tested for the presence of radar with less interference from other STAs.
- Testing channels for radar before using a channel and while operating in a channel.
- Discontinuing operations after detecting radar in the current channel to avoid interference with radar.
- Detecting radar in the current and other channels based on regulatory requirements.
- Requesting and reporting of measurements in the current and other channels.
- Selecting and advertising a new channel to assist the migration of a BSS after radar is detected.