Is 6 GHz Wi-Fi’s 5G?
Unlicensed devices will soon be able to operate in the 6 GHz band. What does this really mean? Spectrum for everyone! Well, almost. Today, April 23, 2020, the Federal Communications Commission (FCC) approved the draft rules submitted by Chairman Ajit Pai that would allocate 1,200 MHz of spectrum available in the 6 GHz band for unlicensed use.
Currently, there are incumbent licensed services operating in that band, and now, with the FCC approval, unlicensed devices would share this spectrum. Part of those rules will protect those already existing licensed services so all networks can operate harmoniously.
There are roughly 4.78 billion mobile devices globally (the equivalent of 62% of the world’s population) currently on carrier networks, and as the number is projected to increase, it will be critical to continue to offload global mobile data traffic to Wi-Fi networks. By the year 2022, Cisco projects that nearly 60% of all global cellular traffic will be offloaded to Wi-Fi.
Making the entire 6 GHz band available is a huge step towards being able to accommodate the increasing capacity on networks. To quote Chairman Pai, “From Wi-Fi routers to home appliances, Americans’ everyday use of devices that connect to the Internet over unlicensed spectrum has exploded. That trend will only continue.” We need to be ready to accommodate it.
A Breakdown of 6 GHz Channel Allocation
The increased available spectrum makes it more important than ever to have a well-planned and properly designed wireless network. According to the approved rules, indoor low-power devices will be permitted to operate across the 6 GHz band. These include devices that require faster data throughput such as those that enable high-definition video streaming and high-performance, wearable, augmented-reality and virtual-reality experiences. The breakdown of neighboring spectrum blocks in 6 GHz is as follows:
- 59 additional 20 MHz channels
- 29 additional 40 MHz channels
- 14 additional 80 MHz channels
- 7 additional 160 MHz channels
Keith R. Parsons, Managing Director at WLAN Pros, provided the below information to compare the spectrum allocation across Wi-Fi frequencies
How will 6 GHz impact wireless design?
Cell Size and Density of APs
Higher frequencies, such as 5 GHz and 6 GHz, produce a shorter wavelength. This means they travel a shorter distance than the longer wavelengths of lower frequencies (from our days in college physics – wavelength and frequency are inversely related, if one is higher, then the other is shorter). Shorter distances for the higher frequencies create smaller cell sizes.
So how will this impact your network? Smaller cell sizes and transmit power limitations will increase the density of APs in your design. One of the most important components of network planning (and costliest if done incorrectly) is determining the right number of APs and where to put them. Incorrect placement or the incorrect number of APs can create major problems for your network, negatively impacting signal strength and channel interference, as well as causing roaming issues. This results in costly network outages, downtime, or loss of productivity.
If you are designing a multi-band network, you will have to pay close attention to the number of APs and make sure you are not buying excessive hardware.
More Attenuation in Higher Frequencies
Another challenge for wireless network design in 6 GHz is attenuation. Higher frequency waves can be more impacted by attenuation than low-frequency waves. This is potentially problematic as you will have to account for the increased attenuation in your network design. You will want to perform a survey to validate the performance of the environment. The challenges don’t stop here. There will be several others that can impact your network design such as roaming. You will want to make sure you account for these challenges as more information is made available for 6 GHz.
Designing for the Future: 6 GHz vs. 5 GHz
In environments such as large public venues (LPV), education, traditional enterprise, and healthcare, a 6 GHz network may make sense due to capacity and Quality of Service (QoS) functions that are critical. In manufacturing and warehousing environments where you need bigger cell sizes, and may have older technology still in use (handheld scanners etc), a 6 GHz design may not be the best route. You will still need to utilize the 2.4 GHz frequency.
As our world continues to consume and innovate using wireless technologies, this expansion plan will increase the amount of available spectrum for Wi-Fi by almost a factor of five, according to the FCC. In a communication from the FCC published today, “The FCC has adopted new rules for the 6 GHz band, unleashing 1,200 megahertz to boost #WiFi and other unlicensed uses to usher in faster, more efficient broadband connections…”.
For information on the FCC vote, click in this file: doc-363945a1.pdf