The FCC Releases Needed Spectrum

The FCC made two moves in the last week concerning spectrum. Chairman Ajit Pai announced intentions to vote later this month to release the entire 1,200 MHz band of 6 GHz spectrum for unlicensed usage. They also awarded special temporary authority for 33 WISPs to use 45 MHz out of the 5.9 GHz band to boost rural fixed broadband during the COVID-19 crisis.

It’s expected that the recommendation for the 6 GHz spectrum will be approved unanimously by FCC Commissioners. This announcement is huge news. This would increase the bandwidth available for WiFi by almost a factor of 5. The WiFi band already carries far more data than any other swath of spectrum and this bolsters WiFi for the next few decades. The order proposes to uses for the new spectrum. The entire 1,200 MHz of frequency would be released for indoor usage at low power. 850 MHz of the band would be released at standard power levels and can be used outdoors in hot spots and for point-to-multipoint fixed wireless networks.

The cellular carriers have been lobbying hard to have some of the bandwidth sold as licensed spectrum. Instead, the FCC order would allocate it all to public use, but allows anybody, including the cellular carriers to use the spectrum subject to automated frequency coordination. That’s the system that senses existing use of the spectrum before allowing a second interfering use. The cellular carriers might elect to use this spectrum heavily, on an as-needed basis, in urban areas, but likely won’t bother in rural areas – freeing this bandwidth mostly for rural broadband usage.

This is big news because until this announcement there was still the possibility that some of the spectrum would be allocated to a licensed auction. The Chairman did say that he was considering making this all public spectrum a year ago, but a decision was never official until now. This is big news for the whole WiFi industry as well, since any spectrum allocated to licensed spectrum would have been off-limits for indoor WiFi use. As I’ve written in other blogs, this new spectrum, along with the introduction of WiFi 6 technology means a massive upgrade in capability for home and office WiFi performance. This should enable multiple simultaneous large-bandwidth uses of bandwidth within the home or office without interference. WiFi 6 also uses techniques that cut down on interference from neighboring hotspots.

The second action by the FCC is interesting. They granted special temporary authority to 33 rural WISPs to use 45 MHz of the 5.9 GHz spectrum for the next 60 days. This will allow these WISPs to beef up rural bandwidth during the COVID-19 crisis. The WISPs report that they are seeing a 35% increase in traffic volumes along with a requests for more bandwidth due to students and employees suddenly working from homes.

The extra bandwidth will allow these ISPs to boost bandwidth since they use software-defined radios that already work in the nearby 5 GHz WiFi spectrum band. I would expect the FCC to continue the temporary use of the spectrum if shelter-in-place extends in some places past the 60-day window.

These temporary uses of the spectrum might presage a more permanent use of this spectrum band. The 5.9 GHz spectrum was set aside many years ago for vehicle-to-vehicle communications. The self-driving and assisted driving vehicle technology has advanced much more slowly than originally anticipated, plus some car manufacturers are using a different spectrum solution for communicating from car to car. The FCC was already considering splitting the spectrum band and cutting the amount of spectrum available to vehicles in half, with the rest likely going to public auction. The cellular carriers claim that they still only have half of the mid-range spectrum they need to support full deployment of 5G, and the FCC seems likely to grab this spectrum for that purpose.

Introducing 6 GHz into WiFi

WiFi is already the most successful deployment of spectrum ever. In the recent Annual Internet Report, Cisco predicted that by 2022 that WiFi will cross the threshold and will carry more than 50% of global IP traffic. Cisco predicts by 2023 that there will be 628 million WiFi hotspots – most used for home broadband.

These are amazing statistics when you consider that WiFi has been limited to using 70 MHz of spectrum in the 2.4 GHz spectrum band and 500 MHz in the 5 GHz spectrum band. That’s all about to change as two major upgrades are being made to WiFi – the upgrade to WiFi 6 and the integration 6 GHz spectrum into WiFi.

The Impact of WiFi 6. WiFi 6 is the new consumer-friendly name given to the next generation of WiFi technology (replaces the term 802.11ax). Even without the introduction of new spectrum WiFi 6 will significantly improve performance over WiFi 5 (802.11ac).

The problem with current WiFi is congestion. Congestion comes in two ways – from multiple devices trying to use the same router, and from multiple routers trying to use the same channels. My house is probably typical, and we have a few dozen devices that can use the WiFi router. My wife’s Subaru even connects to our network to check for updates every time she pulls into the driveway. With only two of us in the house, we don’t overtax our router – but we can when my daughter is home from college.

Channel congestion is the real culprit in our neighborhood. We live in a moderately dense neighborhood of single-family homes and we can all see multiple WiFi networks. I just looked at my computer and I see 24 other WiFi networks, including the delightfully named ‘More Cowbell’ and ‘Very Secret CIA Network’. All of these networks are using the same small number of channels, and WiFi pauses whenever it sees a demand for bandwidth from any of these networks.

Both kinds of congestion slow down throughput due to the nature of the WiFi specification. The demands for routers and for channels are queued and each device has to wait its turn to transmit or receive data. Theoretically, a WiFi network can transmit data quickly by grabbing a full channel – but that rarely happens. The existing 5 GHz band has six 80-MHz and two 160-MHz channels available. A download of a big file could go quickly if a full channel could be used for the purpose. However, if there are overlapping demands for even a portion of a channel then the whole channel is not assigned for a specific task.

Wi-Fi 6 introduces a few major upgrades in the way that WiFi works to decrease congestion. The first is the introduction of orthogonal frequency-division multiple access (OFDMA). This technology allows devices to transmit simultaneously rather than wait for a turn in the queue. OFDMA divides channels into smaller sub-channels called resource units. The analogy used in the industry is that this will open WiFi from a single-lane technology to a multi-lane freeway. WiFi 6 also uses other techniques like improved beamforming to make a focused connection to a specific device, which lowers the chances of interference from other devices.

The Impact of 6 GHz. WiFi performance was already getting a lot better due to WiFi 6 technology. Adding the 6 GHz spectrum will drive performance to yet another level. The 6GHz spectrum adds seven 160 MHz channels to the WiFi environment (or alternately adds fifty-nine 20 MHz channels. For the typical WiFi environment, such as a home in an urban setting, this is enough new channels that a big bandwidth demand ought to be able to grab a full 160 MHz channel. This is going to increase the perceived speeds of WiFi routers significantly.

When the extra bandwidth is paired with OFDMA technology, interference ought to be a thing of the past, except perhaps in super-busy environments like a business hotel or a stadium. Undoubtedly, we’ll find ways over the next decade to fill up WiFi 6 routers and we’ll eventually be begging the FCC for even more WiFi spectrum. But for now, this should solve WiFi interference in all but the toughest WiFi environments.

It’s worth a word of caution that this improvement isn’t going to happen overnight. You need both a WiFi 6 router and WiFi-capable devices to take advantage of the new WiFi 6 technology. You’ll also need devices capable of using the 6 GHz spectrum. Unless you’re willing to throw away every WiFi device in your home and start over, it’s going to take most homes years to migrate into the combined benefits of WiFi 6 and 6 GHz spectrum.

Can 5G Replace WiFi?

Verizon recently posted a webcast with investors where Ronan Dunne, EVP and CEO of the Verizon Consumer Group said that he believed that 5G hotspots using millimeter wave spectrum will eventually displace WiFi in homes.

He cites major benefits of 5G over WiFi. He believes that a 5G network will be more reliable and more secure. He thinks that people will value the safety that comes from having traffic inside their home being encrypted as it rides Verizon’s 5G network compared to the more public nature of WiFi where every neighbor can see a home’s WiFi network.

He also cites the convenience of being able to transfer 5G traffic between networks. He paints a picture where a customer making a call or watching a video using a home 5G hotspot will be able to walk out the door and seamlessly continue the session outside on their cellphone. That’s pretty slick stuff should that ever come to pass.

The picture he’s painting for Verizon investors is a future where homes buy a Verizon 5G subscription to use in place of WiFi. This is part of Verizon’s ongoing effort to find a business case for 5G. His vision of the future is possible, but there are a lot of hurdles for Verizon to overcome to achieve that vision.

It’s going to get harder to compete with WiFi since the technology is getting a lot better with two major upgrades. First, the industry has introduced WiFi 6, which brings higher quality performance, lower latency, and faster data rates. WiFi 6 will use techniques like improved beamforming to greatly reduce interference between WiFi uses within the home.

Even more importantly, WiFi will be incorporating the new 6 GHz spectrum band that will increase bandwidth capabilities by adding seven 160 MHz bands and fourteen 80 MHz bands. It will be much easier to put home devices on separate channels when these new channels are added to the existing channels available on 2.4 and 5 GHz. This means that 5G will be competing against a much improved WiFi compared to the technology we all use today.

Another big hurdle for Verizon to overcome is that WiFi is ubiquitous today. WiFi is built into a huge number of devices, and a homeowner might already own a dozen or more devices capable of using WiFi. Verizon will have to somehow convince homeowners that 5G is so superior that it’s worth replacing the panoply of WiFi devices.

Another hurdle is that there is going to be WiFi vendors painting almost the same picture as Verizon. The makers of WiFi routers are already envisioning future devices that will introduce millimeter-wave spectrum including 5G into the home. There are vendors already working on devices that will provide both WiFi 6 and 5G using millimeter-wave connections simultaneously, using the publicly available 60 GHz V band. These solutions envision offering everything that Verizon can do, except the ability to roam seamlessly in and out of a home – and it will be done by selling a box instead of a new monthly subscription.

Another interesting hurdle to switching home networks to 5G is that there might be separate 5G solutions for each cellular carrier that uses different bands of spectrum. It’s relatively easy for device makers today to build a cellphone or other device that can use different cellular carriers because the carriers all use similar spectrum. But as each cellular company picks a different mix of frequencies moving forward, there is likely going to be cellphones and other devices that are specific to one carrier. It’s impossible to build a cellphone with today’s battery technology that can receive a huge range of spectrums – the multiple antenna systems would drain a cellphone dry in no time.

The largest hurdle of all is that WiFi is free to use after buying a WiFi router or meshed WiFi devices for the home. There is no monthly subscription fee to use the wireless WiFi connections within the home. Verizon clearly foresees a world where every home has a new monthly subscription to use its in-home 5G network.

Mr. Dunne makes one good point. It’s becoming increasingly clear that public WiFi networks are susceptible to hacking. A 5G network controlled by a carrier should be a lot safer than a WiFi hotspot managed by a coffee shop. The big question is if this enough incentive for people to buy 5G-capable devices or for coffee shops to switch to 5G networks. Even should coffee shops go with a 5G solution, will homes follow suit?

Mr. Dunne vision has an underlying assumption that people will value data security enough to be willing to pay more for it. He envisions people choosing a managed network when they have a choice. He could be right, and perhaps there will be enough data breaches in coming years with WiFi that the paradigm will change from WiFi to 5G. But it’s going to be incredibly hard to dislodge WiFi, particularly when it’s evolving and improving along with 5G.

Even if Mr. Dunne is right, this shift is not coming soon, probably not within this decade. For now, WiFi has won the device war and any shift to 5G would drag out over many years. It’s going to be incredibly difficult for the cellular carriers to convince everybody to switch to 5G.

I sympathize with Mr. Dunne’s dilemma. Investors want to understand where the revenues will come from to fund the expensive upgrades to 5G. Verizon and the other cellular carriers have tossed out a lot of ideas, but so far none of them have stuck to the wall.  Investors are getting rightfully nervous since there doesn’t appear to be any significant 5G revenues coming in the next few years. The carriers keep painting pictures of an amazing 5G future as a way to not have to talk about lack of 5G revenues today.

Happy Birthday Wi-Fi

This year is the twentieth anniversary of the formation of the Wi-Fi Alliance and the launch of commercial Wi-Fi. Wi-Fi has become so ubiquitous in our lives that it’s hard to believe that it’s only been twenty years since all broadband connections came with wires.

In 1999 most people were still using dial-up and that’s the year when early adapters started buying DSL. I remember having incredibly long phone cords so that I could use my laptop at different places around the house. When I bought DSL, I became tied to the desk with the DSL modem because I couldn’t find equally long cords to carry DSL all over the house.

I remember the day I bought my first Linksys Wi-Fi router. At that time, I think the only device in my home that would talk to Wi-Fi was my laptop. I was able to use that laptop everywhere around the house, and I remember how liberating it felt to be able to use the laptop on the front porch. I got my first carrier-class Wi-Fi router when I upgraded to fiber on Verizon FiOS. Even then I think the only devices in my house that communicated with the Wi-Fi router were a desktop and some laptops – the world had not yet started to build Wi-Fi into numerous devices. Today my home is crammed full of Wi-Fi-capable devices and it’s hard to imagine going without the wireless technology.

There’s an article in the current Wired by Jeff Abramowitz discussing how Wi-Fi as we know it almost didn’t happen. At the time that 802.11b was introduced there was a competing technology called HomeRF that was being pushed as a home wireless solution. We easily could have ended up with HomeRF used in the home and 802.11b used in the office. That would have meant no easy transition of devices from office to home, which would likely have stymied the ubiquitous Wi-Fi we have today.

The growth of Wi-Fi required free spectrum to thrive, and for that, we can thank microwave ovens. Microwave ovens were first developed in the 1940s and emitted radiation the 2.45 GHz frequency. In the 1960s practically every home bought a microwave oven, and at that time the devices didn’t have great shielding. Since the microwave ovens polluted the spectrum on both sides of the 2.45 GHz band, the FCC decided in 1985 to add frequency bands on both sides of that spectrum, creating the ISM band that was open for anybody to use. With the radio technology available at the time nobody wanted to put any commercial usage too close to leaky microwave ovens. Since then, microwave ovens have better shielding and radios are more accurate in pinpointing narrow channels, and we can now use most of what the FCC had considered in 1985 to be junk spectrum.

I am amused every time I hear somebody in the industry say that broadband is going wireless – and by that, they mean 5G cellular. Today the average cellphone customer uses about 6 GB of cellular data per month. What the cellphone companies don’t talk about is that the average cellphone user also consumes three times that much data each month on Wi-Fi connection. The fact is that our cellphones are mostly Wi-Fi devices that can change to cellular data when we’re out of reach of our homes, schools, and offices.

Wi-Fi is about to take another big leap forward as WiFi 6 is being officially released this month. This newest version of Wi-Fi uses less energy, reduces latency, increases performance in crowded wireless environments, and allows for faster speeds. Wi-Fi has gotten a lot more sophisticated with the introduction of techniques like beamforming and the technology is light years ahead of what first came out in 1999. In those early days, a Wi-Fi modem was just good enough to handle the 1 Mbps DSL and cable modems broadband of the day.

Device manufacturers love Wi-Fi. Estimates vary, but there are predictions that there will be something like 10 billion worldwide Wi-Fi connected devices in 2020 and 22 billion by 2025 – which would be nearly three Wi-Fi devices for every person on the planet. Those are unbelievable numbers for a technology that only came into existence twenty years ago. The manufacturers must be thrilled knowing that we’ll all be buying new devices to upgrade to Wi-Fi 6 over the next few years.

If Wi-Fi was a person, I’d bake them a cake or buy them a drink to honor this birthday. I’ll have to settle for thanking all of those who have contributed over the years to turn the Wi-Fi concept into the robust products that have changed all of our lives.

5G and Home IoT

I’ve been asked a lot recently about the potential future of 5G – everybody in the industry wants to understand the potential threat from 5G. One of the biggest proposed uses for 5G is to connect IoT devices to the cloud. Today I’m going to look at what that might mean.

It’s clear that 5G cellular will be the choice for connecting to outdoor IoT sensors. Sensors for farm equipment in rural areas or for outdoor weather and traffic sensors in urban areas are going to most easily handled by 5G cellular since the technology will eventually be everywhere. 5G is particularly suited for serving IoT devices due to frequency slicing where just the right amount of bandwidth, large or small, can be allocated to each small outdoor sensor. 5G has another interesting feature that will allow it to poll sensors on a pre-set schedule rather than have the sensor constantly trying to constantly connect – which will reduce power consumption at the sensor.

It’s clear that the cellular carriers also have their eye on indoor IoT devices. It’s harder to say that 5G will win this battle because today almost all indoor devices are connected using WiFi.

There are a couple of different 5G applications that might work in the indoor environment. The cellular carriers are going to make a pitch to be the technology of choice to connect small inside devices. In my home I can get a good cellular signal everywhere except in the old underground basement. There is no question that cellular signal from outside the home could be used to connect to many of the smaller bandwidth applications within the home. I can’t see any technical reason that devices like my Amazon Echo or smart appliances couldn’t connect to 5G instead of WiFi.

But 5G cellular has a number of hurdles issues to overcome to break into this market. I’m always going to have a wired broadband connection to my home, and as long as that connection comes from somebody other than one of the big cellular carriers I’m not going to want to use 5G if that means paying for another monthly subscription to a cellular provider. I’d much rather have my inside devices connected to the current broadband connection. I also want all of my devices on the same network for easy management. I want to use one hub to control smart light switches or other devices and want everything on the same wireless network. That means I don’t want some devices on WiFi and others on cellular.

One of the sales pitches for 5G is that it will be able to easily accommodate large numbers of IoT connections. Looking into the future there might come a time when there are a hundred or more smart devices in the house. It’s not that hard to picture the Jetson’s house where window shades change automatically to collect or block sunlight, where music plays automatically when I enter a room, where my coffee is automatically ready for me when I get out of bed in the morning. These things can be done today with a lot of effort, but with enough smart devices in a home these functions will probably eventually become mainstream.

One of the limitations of WiFi today is that it degrades in a busy environment. A WiFi network pauses each time it gets a new request for a connection, which is the primary reason it’s so hard to keep a good connection in a busy hotel or convention center.

However, the next generation with WiFi 6 is already anticipating these needs in the home. WiFi can adopt the same frequency slicing used by 5G so that only a small portion of a channel can be used to connect to a given device. Events can be scheduled on WiFi so that the network only polls certain sensors only periodically. The WiFi network might only interact with the smart coffee pot or the smart window shades when something needs to be done, rather than maintaining a constantly open channel. It’s likely that the next iterations of WiFi will become nearly as good as 5G for these functions within a closed home environment.

There is an even better solution that is also being discussed. There’s no reason that indoor routers can’t be built that use both WiFi and 5G frequencies. While the cellular companies are gobbling up millimeter wave spectrum, as long as there is an unlicensed slice of spectrum set aside for public use it will be possible to deploy both WiFi on mid-range frequencies and 5G on millimeter wave frequencies at the same time. This would blend the benefits of both technologies. It might mean using WiFi to control the smart coffee pot and indoor 5G to connect to the smart TV.

Unfortunately for the cellular carriers, these duel-function routers won’t need them. The same companies that make WiFi routers today can make combination 5G / WiFi routers that work with the full range of unlicensed spectrum – meaning no revenue opportunity for the cellular carriers. When I look at all of the issues I have a hard time seeing 5G cellular becoming a preferred technology within the home.

 

5G vs. WiFi

The big cellular carriers envision a future where every smart device is connected to their cellular networks rather than to WiFi. They envision every home having to pay a monthly subscription to maintain connectivity for their wired devices. They envision every new car and truck coming with a subscription to cellular service.

I notice that the cellular providers talk about generating IoT revenues, but they’re never specific that the real vision is for everybody to buy additional cellular subscriptions. Most IoT applications will be low-bandwidth yet the carriers have been spreading the false message that 5G is all about faster broadband. I just saw another ludicrous article yesterday predicting how 5G was going to bring mobile gigabit broadband to rural America – a pure fantasy that is being fed by the public relations machines at Verizon and AT&T.

We aren’t seeing much press about the most important aspect of the new 5G specifications – that each cell site will be able to make up to 100,000 simultaneous connections. This isn’t being done for cellphones. It’s rare these days except in a few over-crowded places for a cellular call not to be connected. Placing a few small cell sites at the busiest places in most cities could solve most cellular bottlenecks without an upgrade to 5G.

The 100,000 connections give the wireless carriers the tool that can make a connection to every smart TV, smart washer and dryer, home video camera, burglar alarm sensor and every other wired device in a home. The big carriers are launching a direct challenge to WiFi as the wireless technology of choice for connecting our devices.

AT&T and Verizon envision every home having a new $10, $20 or $30 subscription to keep all of the devices connected. They also envision becoming the repository of all IoT data – moving them in front of Google and others in the chase for collecting the big data that drives advertising revenues. This is something they definitely don’t talk about.

It doesn’t take much of a thought exercise to understand that 5G is not about faster cellular service. Cellular subscribers will gladly take faster cellular broadband, but they probably aren’t willing to pay more for it. T-Mobile is already making that clear by announcing that they won’t charge more for 5G. The carriers are not going to spend tens of billions to implement 5G cellular technology that doesn’t drive the new revenues needed to pay for it. 5G is about IoT, plain and simple.

Today all of our home devices use WiFi. While WiFi is far from perfect, it seems to do an adequate job in connecting to the video camera at the front door, the smart TV, and the sensors in various appliances and devices around the home. WiFi has a few major advantages over cellular broadband – it’s already in our homes and connected to our devices and doesn’t require an additional monthly subscription.

I think people will resist another forced subscription. HP recently reported that the vast majority of their customers that buy 4G LTE-enabled laptops disable the cellular connection almost as soon as the new computer is out of the box. In this day of cellphones, very few car owners sign-up for the cellular subscription for OnStar when the free trial expires. I know that I personally would not buy a home device that eventually needed another cellular subscription to function.

The cellular carriers make a valid point in saying that WiFi is already growing inadequate for busy homes. But there are already short-term and long-term fixes on the way. The short-term fix is the upcoming migration to WiFi 6 using the 802.11ax standard. The new WiFi will better use MIMO antennas, frequency slicing and other techniques to allow for prioritization of devices and a more reliable connection to multiple devices.

The ultimate indoor broadband network will be a combination of WiFi and millimeter wave, or even faster spectrum. Higher frequency spectrum could provide bandwidth for the devices that use big bandwidth while keeping other devices on mid-range spectrum WiFi – getting the best from both sets of spectrum. That combination will allow for the easy integration, without interference for the connection of gigabit devices and also of tiny sensors that only communicate sporadically.

This is not the future that AT&T and Verizon want, because this is a world controlled by consumers who buy the wireless boxes that best suit them. I envision a future indoor-only wireless network that won’t require licensed spectrum or a cellular subscription since the millimeter waves and other higher frequencies won’t pass outdoors through walls.

The cellular carriers will have a monopoly on the outdoor sensor market. They will undoubtedly make the connections to smart cars, to smart agriculture, and to outdoor smart city sensors. But I think they will have a huge uphill battle convincing households to pay another monthly subscription for something that can be done better using a few well-placed routers.