What is UNII-7?
UNII-7 is the third of the four sub-bands that make up the 6 GHz Wi-Fi band. It covers 6.525 to 6.875 GHz, a 350 MHz block with 20 MHz channels 117 to 181, making it the second largest 6 GHz sub-band after UNII-5. UNII stands for Unlicensed National Information Infrastructure, the FCC's name for these bands. Wi-Fi 6E and Wi-Fi 7 devices use it.
The four 6 GHz sub-bands
| Sub-band | Frequency range | 20 MHz channels | US access point rules (FCC) |
|---|---|---|---|
| UNII-5 | 5.925 to 6.425 GHz | 1 to 93 | Low-power indoor, or standard power with AFC |
| UNII-6 | 6.425 to 6.525 GHz | 97 to 113 | Low-power indoor; no standard power |
| UNII-7 | 6.525 to 6.875 GHz | 117 to 181 | Low-power indoor, or standard power with AFC |
| UNII-8 | 6.875 to 7.125 GHz | 185 to 233 | Low-power indoor; no standard power |
Together the four sub-bands span 1,200 MHz, with 59 channels at 20 MHz. 6 GHz channel numbers start over at 1 and go up by 4. A channel's center frequency is 5.950 GHz plus 5 MHz times the channel number, so channel 117 is centered at 6.535 GHz. Channel 185 is centered exactly on the 6.875 GHz line between UNII-7 and UNII-8 and is listed here with UNII-8.
US rules for UNII-7
In the United States (FCC), UNII-7 allows both main classes of access point:
- Low-power indoor (LPI): indoor-only access points at limited power, with no database check.
- Standard power: higher power, indoors or outdoors, but only on the channels and power levels an AFC (Automated Frequency Coordination) system approves for the access point's location. AFC protects the licensed fixed microwave links that also use this spectrum.
UNII-7 has no DFS requirement. DFS is a 5 GHz rule.
Using UNII-7 in practice
UNII-5 and UNII-7 are the only 6 GHz sub-bands where US rules allow standard power, so they're where outdoor and longer-range 6 GHz Wi-Fi happens. The 6 GHz channel grid doesn't line up exactly with the sub-band edges, so some 80 and 160 MHz channels straddle UNII-6 and UNII-7, or UNII-7 and UNII-8. The Wi-Fi Alliance's preferred scanning channels (PSCs) in this sub-band are 117, 133, 149, 165 and 181. Many countries outside the US, including the European Union, opened only the 6 GHz spectrum below 6.425 GHz, so UNII-7 channels may not be available there.
For the CompTIA A+ exam
Core 1 (220-1201) objective 2.2 lists 6 GHz among the Wi-Fi frequencies and covers channel regulations. UNII-7 isn't named in the objectives. Know that the 6 GHz band is split into sub-bands with different power rules, and that 6 GHz needs a Wi-Fi 6E or Wi-Fi 7 device.