On 23 April 2020 the US Federal Communications Commission (FCC) voted unanimously to open the 6 GHz band, 5.925 to 7.125 GHz, for unlicensed use. That added 1,200 MHz of spectrum for Wi-Fi, more than doubling what Wi-Fi had in the 2.4 GHz and 5 GHz bands combined, and created the room that Wi-Fi 6E devices were designed to use. Devices with the new antennas and chipsets were expected to start arriving later in 2020.
Key takeaways
- The FCC opened 1,200 MHz at 6 GHz for unlicensed devices in a unanimous vote on 23 April 2020.
- Wi-Fi 6E is Wi-Fi 6 (IEEE 802.11ax) extended into the new band.
- Two classes of operation were allowed: Low Power Indoor, and Standard Power indoor and outdoor under automated frequency coordination (AFC).
- The extra spectrum makes room for many more wide 80 MHz and 160 MHz channels, which is what lifts real-world throughput.
What the FCC decided
The FCC called the move a benefit to consumers that would "further our leadership in next-generation wireless technologies, including 5G." An industry-funded study by Columbia professor Raul Katz backed that view and suggested the decision could generate more than $180 billion in US revenue by 2025 (as published in 2020; an estimate, not a measured outcome).
The 6 GHz band was already used by licensed services such as fixed microwave links for utilities and public safety, and by satellite uplinks. The rules were written to let Wi-Fi share the band without interfering with them.
The rules for unlicensed use
The decision came with a set of rules. Two types of unlicensed operation are allowed:
| Class | Where | Frequency range | Main condition |
|---|---|---|---|
| Low Power Indoor (LPI) | Indoors only | The whole 1,200 MHz | Low transmit power; access points must not be weatherproof or battery powered |
| Standard Power | Indoors and outdoors | About 850 MHz of the band (U-NII-5 and U-NII-7) | Must check an automated frequency coordination (AFC) database before transmitting, to protect fixed links |
As commonly summarised, LPI access points are limited to a power spectral density of 5 dBm/MHz (30 dBm maximum EIRP), and standard power devices to 23 dBm/MHz (36 dBm). Sundar Sankaran has written a clear summary of the key regulatory requirements: read on for more details here.
Why it matters
Channel width drives Wi-Fi throughput, and the older bands are crowded. At 5 GHz there are only a couple of 160 MHz channels in practice, and they often overlap with radar protection rules. The 6 GHz band holds fourteen 80 MHz channels or seven 160 MHz channels, with no legacy Wi-Fi devices to slow things down, because only 6E-capable devices can use it.
A rough, illustrative example: a two-stream Wi-Fi 6 client on a 160 MHz channel has a top PHY rate of about 2.4 Gb/s. On 80 MHz, the top rate halves to about 1.2 Gb/s. With seven 160 MHz channels available, neighbouring apartments or offices can each run a wide channel instead of fighting over one.
For chip designers, the band meant new RF front ends, filters that separate 5 GHz and 6 GHz, and radios that reach up to 7.125 GHz. Later in the decade it also became the base for Wi-Fi 7 (IEEE 802.11be), which adds 320 MHz channels that fit only in the 6 GHz band.
FAQ
Is Wi-Fi 6E a new standard?
No. It is Wi-Fi 6 (802.11ax) operating in the 6 GHz band, under the Wi-Fi Alliance's 6E certification.
Can older Wi-Fi devices use 6 GHz?
No. A device needs a 6 GHz-capable radio and antenna, so existing phones and laptops did not gain access.
Did other countries follow?
Yes, at different speeds. The UK and the EU opened the lower 500 MHz of the band, while others such as South Korea and Brazil opened all 1,200 MHz. Rules vary by country, so check the local regulator.
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