802.11ac is a Wi-Fi standard that was introduced in 2013 to provide faster wireless network speeds. It builds on previous Wi-Fi standards like 802.11n by utilizing wider bandwidth channels, more antennas for increased throughput, and other performance enhancements.
One of the key questions around 802.11ac networks is whether they operate solely in the 5 GHz frequency band or if they are also compatible with 2.4 GHz. The answer is that 802.11ac can work in both the 2.4 GHz and 5 GHz frequencies. However, maximum performance is achieved in the less crowded 5 GHz band.
802.11ac Frequency Bands
Here is a more detailed overview of how 802.11ac utilizes different wireless spectrum bands:
- 5 GHz band – 802.11ac is designed to primarily use the 5 GHz frequency band which offers more available channels and less interference from other devices compared to 2.4 GHz. By using wider 80 and 160 MHz channels, 802.11ac can achieve very high theoretical speeds up to 6.93 Gbps.
- 2.4 GHz band – For backwards compatibility reasons, 802.11ac access points still provide connectivity on 2.4 GHz using 20 MHz channels up to 144 Mbps. This allows older 2.4 GHz clients to connect to the network. However, two 802.11ac devices would use 5 GHz for best performance.
So in summary, 802.11ac does work on 2.4 GHz to maintain compatibility with older Wi-Fi devices. But it is intended as a 5 GHz technology to deliver the fastest wireless speeds to newer clients that also have 802.11ac radios.
Benefits of 802.11ac in 2.4 vs 5 GHz
There are some tradeoffs when operating 802.11ac on 2.4 GHz versus 5 GHz:
2.4 GHz Benefits
- Broader range through walls and obstacles
- Support for older 2.4 GHz client devices
5 GHz Benefits
- Less interference and less crowded
- Much higher available bandwidth
- Faster maximum speeds up to 6.93 Gbps
- More spatial streams (up to 8)
As you can see, both frequency bands have their place depending on your needs. But the superior performance of 802.11ac is achieved by using 80 or 160 MHz channels in the less congested 5 GHz band when possible.
Typical 802.11ac Performance
In real-world usage, a typical 802.11ac network would utilize both 2.4 GHz and 5 GHz at the same time:
- 2.4 GHz band – Supports older 2.4 GHz devices at speeds up to 144 Mbps
- 5 GHz band
- 80 MHz channel width – Speeds up to 1.3 Gbps
- 160 MHz channel width – Speeds up to 2.6 Gbps
So while 6.93 Gbps is the technical maximum of 802.11ac using 160 MHz channels and 8 spatial streams, most current devices max out at 1.3 to 2.6 Gbps speeds. Still a dramatic improvement over older Wi-Fi standards.
As client devices catch up with 4×4 and 8×8 antenna configurations in the coming years, we will continue to see increased speeds. But on both 2.4 GHz and 5 GHz, 802.11ac provides a major boost in throughput compared to older Wi-Fi versions.
- 802.11ac can operate on both 2.4 GHz and 5 GHz frequency bands
- 2.4 GHz provides broader compatibility with older Wi-Fi devices
- 5 GHz with wider channel widths enables maximum 802.11ac performance
- Typical real-world speeds range from 433 Mbps up to 2.6 Gbps
- Future advances will enable multi-gigabit throughput to catch up with the 6.93 Gbps theoretical peak
In summary, while 802.11ac is primarily designed for high-speed 5 GHz networks, it does maintain backwards compatibility with 2.4 GHz clients. Operating at 2.4 GHz allows older devices to connect, but utilizes slower speeds up to 144 Mbps. To achieve gigabit+ throughput, 802.11ac utilizes 80 or 160 MHz channel widths in the less crowded 5 GHz bands. As device capabilities improve over time, 802.11ac remains future-proof to deliver multi-gigabit wireless networking to upcoming client devices for years to come.
Frequently Asked Questions
Q: What is 802.11ac?
A: 802.11ac is a Wi-Fi standard introduced in 2013 that provides faster wireless network speeds using technologies like wider bandwidth channels, beamforming, and more antennas. It builds on previous standards like 802.11n.
Q: Does 802.11ac work on 2.4 GHz?
A: Yes, 802.11ac access points are backwards compatible with 2.4 GHz to support older wireless clients. However, performance is limited to slower speeds on 2.4 GHz.
Q: What Wi-Fi speeds can 802.11ac achieve on 2.4 GHz?
A: When operating on traditional 20MHz-wide 2.4 GHz channels, maximum link rates for 802.11ac are 144 Mbps. This matches the fastest speeds previously achievable by 802.11n technology.
Q: Is 802.11ac faster on 5 GHz?
A: Yes, much faster speeds are enabled by using wider 80 and 160 MHz channels in the less congested 5 GHz bands. This allows for up to 1.3 Gbps on 80 MHz and up to 6.93 Gbps theoretical peak on 160 MHz channels.
Q: What typical speeds can I expect from 802.11ac?
A: Most current 802.11ac devices operate on 80 MHz channels at up to 1.3 Gbps speeds. High-end devices may achieve near 2.6 Gbps on 160 MHz channels. These are real-world speeds with some overhead, not absolute theoretical peak rates.
Q: Does an 802.11ac router support older devices?
A: Yes, 802.11ac routers maintain backwards compatibility with older Wi-Fi devices so you can have a mix of newer 802.11ac as well as older 802.11n or 802.11g devices all connected to one wireless network.
Q: Should I disable 2.4 GHz and only use 5 GHz?
A: No, it is recommended to leave both 2.4GHz and 5GHz active to service different types of devices. Some older Wi-Fi devices may only work on 2.4 GHz. All modern Wi-Fi devices will take advantage of 5 GHz for better performance when available. The device itself chooses best available band.
Q: What are the range differences between 2.4 GHz and 5 GHz?
A: Generally 2.4 GHz provides wider range through walls while 5 GHz performance degrades faster over distance but offers much higher speeds when in close range. Having both bands available provides a good balance for distance and speed.
Q: Will 160 MHz channels cause more interference?
A: Yes, the wider 160 MHz channels have greater risk of overlapping with neighboring Wi-Fi networks so it’s ideal to use the cleanest channels based on a Wi-Fi site survey. Dynamic channel management helps avoid interference by switching channels automatically.
Q: Is 802.11ac compatible with 802.11a/b/g/n?
A: Yes, 802.11ac Wi-Fi routers retain compatibility with all earlier Wi-Fi devices so you can have a mix of different standards connected to one wireless network. But only 802.11ac clients can achieve maximum performance speeds.
Q: What identifies an 802.11ac device?
A: Devices that support 802.11ac Wi-Fi will clearly state that standard along with technologies such as beamforming and higher channel width support. The number of antennas (1×1, 2×2 etc) determines overall throughput capability. An easy way to tell is also 5 GHz support.
Q: How can I get maximum 802.11ac performance?
A: Using 80 or 160 MHz-wide channels in a clean 5 GHz radio environment unleashes the full performance capabilities of 802.11ac. Also having compatible Wi-Fi client devices such as laptops, phones and tablets that use the latest Wi-Fi chips and antennas.