Millimeter Wave Cellular Service

Verizon is claiming to have the first real-world deployment of fast 5G cellular service. They launched an early version of what they are calling 5G in downtown Chicago and Minneapolis. This launch involves the deployment of millimeter wave spectrum.

A review of the cellular performance in FierceWireless showed exactly what was to be expected. This new service will only be available from a few cell sites in each city. For now the service can only be received using a Motorola Z3 handset that has been modified with a 5G Moto Mod adapter.

As would be expected, the millimeter wave broadband was fast, with peak speed measured at 500 Mbps. But also as expected, the coverage area is small, and millimeter wave spectrum is easily blocked by almost any impediment. Walking inside a building or around the corner of a building killed the broadband signal. The signal speed cut in half when received through a window. When not in the range of the millimeter wave signal the phone reverts to 4G, because Verizon is not yet close to implementing any actual 5G standards. This was not a trial of 5G technology – it’s a trial that shows that millimeter wave spectrum can carry a lot of data. That is especially easy to demonstrate when there are only one or two users on a given cell site.

Verizon announced a fee of $10 per month for the faster data speed, but almost immediately said the fee will be waived. This launch is another marketing gimmick letting Verizon get headlines proclaiming 500 Mbps cellular data speeds. The reviewer noted that the Verizon store in downtown Chicago was not ready to provide the product to anybody.

There are big issues with using millimeter wave spectrum for cellular service. I first ask what a cellphone user can do with that kind of speed. A cellphone can already be used to stream a video on a decent 4G connection. Other than software updates there isn’t any real need to download big files on a cellphone. It’s unlikely that the cellular carriers are going to let you tether speeds of that magnitude to a computer.

The other big issues will be the real-life limitations of millimeter wave spectrum outdoors. Since the frequency won’t pass through walls, this is strictly going to be an outdoor walking technology. As the FierceWireless review showed, it’s extremely easy to walk out of coverage. A cellular carrier will need to provide multiple cell sites in very close proximity in order to cover a given area.

It’s hard to think that there will ever be many subscribers willing to pay $10 more per month for a product with these limitations. How many people care about getting faster data speed outside, and only in areas of a city that are close to 5G transmitters? Would many cellular customers pay more so that they could save a few minutes per month to download software updates?

It’s hard to envision that the incremental revenues from customers will ever justify the cost of deploying multiple cell sites within close proximity of each other. T-Mobile already announced that they don’t plan to charge extra for 5G data when it’s available – there is no incentive to offer the product if there is no additional revenue.

What I found interesting is that Verizon also announced that they will be launching this same product in 20 additional urban markets soon, with 30 markets by the end of the year. The company will be using this launch to promote the new Galaxy S10 5G phone that will be able to utilize the millimeter wave spectrum. Verizon is touting the new service by saying that it will provide access to faster streaming, augmented-reality, gaming, and consumer and business applications.

If anything, this launch is a gimmick to sell more of the expensive 5G handsets. I wonder how many people will buy this phone hoping for faster service, only to realize that they have to stand outside close to a downtown millimeter wave cell site to use it. How many people want to go outside to enjoy faster gaming or augmented reality?

This is not to say that millimeter wave spectrum doesn’t have value, but that value will manifest when Verizon or somebody offers an indoor 5G modem that’s connected to a landline broadband connection. That would enable a cellphone to connect to faster gaming or augmented reality. That has some definite possibilities, but that is not cellular service, but rather an indoor broadband connection using a cellphone as the receiver.

I’m really starting to hate these gimmicks. Verizon and AT&T are both painting a false picture of 5G by making everybody think it will provide gigabit speeds everywhere – something that is not even listed as a goal of the 5G specifications. These gimmicks are pure marketing hype. The companies want to demonstrate that they are cutting edge. The gimmicks are aimed even more for politicians who the carriers are courting to support deregulation of broadband in the name of 5G. In the cease of this particular gimmick, Verizon might sell more Samsung 5G phones. But the gimmicks are just gimmicks and this trial is not a real product.

What Are Small Cells?

By far the most confusing industry term that is widely used today is ‘small cell’. I see at least a couple of different articles every day talking about some aspect of small cell deployment. What becomes quickly clear after reading a few such articles is that the small cell terminology is being used to describe a number of different technologies.

A lot of the blame for this confusion comes from the CTIA, the industry group that representing the large cellular carriers. As part of lobbying the FCC last year to get the ruling that allows the carriers to deploy devices in the public rights-of-way the CTIA constantly characterized small cell devices to be about the size of pizza boxes. In reality, there are devices that range from the size of a pizza box up to devices the size of dorm refrigerators.

There are a number of different kinds of deployments all being referred to as small cells. The term small cell brings to mind the idea of devices hung on poles that perform the same functions as the big cellular towers. Fully functional pole-mounted cellular sites are not small devices. The FCC set a limit for a pole-mounted small cell to be no larger than 28 cubic feet, and a cell tower replacement device will use most of that allotted space. Additionally, a full cell tower replacement device generally requires a sizable box of electronics and power supply that sits on the ground – often in cabinets the size of the traditional corner mailbox.

These cell-tower replacements are the devices that nobody wants in front of their house. They are large and can be an eyesore. The cabinets on the ground can block the sidewalk – although lately the carriers have been getting smarter and are putting the electronics in an underground vault. These are the big ‘small cell’ devices that are causing safety concerns for line technicians from other utilities that have to worry about working around the devices to fix storm damage.

Then there are the devices that actually are the size of pizza boxes. While they are being called small cells just like to giant boxes, I would better classify these smaller devices as cellular repeaters. These smaller devices re-originate cellular signals to boost coverage in cellular dead spots. I happen to live in a hilly city and I would love to see more of these devices. Cellular coverage here varies widely block by block according to line-of-sight to the big cellular towers. Cellular carriers can boost coverage in a neighborhood by placing one of these devices within sight of a large tower and then beaming from there to cover the dead spots.

If you look at the industry vendor web sites they claim shipment of millions of small cell sites last year. It turns out that 95% of these ‘small cell’ devices are indoor cellular boosters. Landlords deploy these in office buildings, apartment buildings and other places where cellular coverage is poor. Perhaps the best terminology to describe these devices is a cellular offload device that relieves traffic on cell sites. The indoor units use cellular frequencies to communicate with cellphones but then dump cellular data and voice traffic onto the broadband connection of the landlord. It turns out in urban downtowns that 90% plus of cellular usage is done indoors, and these devices help to meet urban demand cellular without the hassle of trying to communicate through the walls of larger buildings.

The next use of the term small cell is for the devices that Verizon recently used to test wireless broadband in a few test markets. These devices have nothing to do with cellular traffic and would best be described as wireless broadband loops. Verizon is using millimeter wave spectrum to beam broadband connections for a thousand feet or so from the pole-mounted devices.

The general public doesn’t understand the wide array of different wireless devices that are being deployed. The truly cellular devices, for now, are all 4G devices that are being used by the cellular carriers to meet the rapidly-growing demand for cellular data. The industry term for this is densification and the carriers are deploying full cell-tower substitute devices or neighborhood repeaters to try to relieve the pressure on the big cellular towers. These purely-cellular devices will eventually handle 5G when it is rolled out over the next decade.

The real confusion I see is that most people now equate ‘small cell’ with fast data. I’ve talked to several cities recently who thought that requests for small cell attachments mean they are going to get gigabit broadband. Instead, almost every request for a small cell site today is for the purpose of beefing up the 4G networks. These extra devices aren’t going to increase 4G data speeds, aren’t bringing 5G and are definitely not intended to beam broadband into people’s homes. These small cells are being deployed to divvy up the cellular traffic to relieve overloaded cellular networks.

False Advertising for 5G

As has been expected, the wireless carriers are now actively marketing 5G cellular even though there are no actual 5G deployments. The marketing folks are always far in front of the engineers and are proclaiming 5G today much in the same way that they proclaimed 4G long before it was available.

The perfect case in point is AT&T. The company announced the launch of what they are calling 5G Evolution in 239 markets. They are also claiming they will be launching what they are calling standards-based 5G in at least 19 cities in early 2019.

The 5G Evolution product doesn’t contain any part of the new 5G standards. Instead, 5G Evolution is AT&T’s deployment of 4G LTE-Advanced technology, which can be characterized as their first fully-compliant 4G product. This is a significant upgrade that they should be proud of, but I guess their marketing folks would rather call this an evolutionary step towards 5G rather than admit that they are finally bringing mature 4G to the market – a claim they’ve already been making for many years.

What I find most annoying about AT&T’s announcement is the claim that 5G Evolution will “enable peak theoretical wireless speeds for capable devices of at least 400 megabits per second”, although their footnote goes on to say that “actual speeds are lower and will vary”. The 4G standard has been theoretically capable of speeds of at least 300 Mbps in a lab setting since the standard was first announced – but that theoretical speed has no relevance to today’s 4G network that generally delivers an average 4G speed of less than 15 Mbps.

This is like having a fiber-to-the-home provider advertise that their product is capable of speeds of 159 terabits per second, although actual speeds might be something less (that’s the current fastest speed achieved on fiber by scientists at the NICT Network System Research Institute in Japan). The intent of the statement on the AT&T website is clearly aimed at making people think they will soon be getting blazingly fast cellular data – which is not true. This is the kind of false advertising that is overstating the case for 5G (and in this case for 4G) that is confusing the public, politicians and regulators. You can’t really blame policy-makers for thinking that wireless will soon be the only technology we will need when the biggest wireless provider shamelessly claims speeds far in excess of what they will be ever be deploying.

AT&T’s second claim of launching standards-based mobile 5G in 19 markets is a little closer to the truth, but is still not 5G cellular. That service is going to deploy millimeter spectrum hotspots (a technology that is being referred to as Mi-Fi) in selected locations in 19 cities including Las Vegas, Los Angeles, Nashville, Orlando, etc.

These will be true hotspots, similar to what we see in Starbucks, meaning that users will have to be in the immediate vicinity of a hotspot to get the faster service. Millimeter wave hotspots have an even shorter propagation distance than normal WiFi hotspots and the signal will travel for a few hundred feet, at best. The hotspot data won’t roam and will only work for a user while they stay in range of a given hot spot.

AT&T hasn’t said where this will be deployed, but I have to imagine it will be in places like big business hotels, convention centers and indoor sports arenas. The deployment serves several purposes for AT&T. In those busy locations it will provide an alternate source of broadband for AT&T customers who have a phone capable of receiving the Mi-Fi signal. This will relieve the pressure on normal cellular data locally, while also providing a wow factor for AT&T customers that get the faster broadband.

However, again, AT&T’s advertising is deceptive. Their press releases make it sound like the general public in these cities will soon have much faster cellular data, and they will not. Those with the right phone that find themselves in one of the selected venues will see the faster speeds, but this technology will not be deployed to the wider market in these cities. Millimeter wave hotspots are an indoor technology and not of much practical use outside. The travel distances are so short that a millimeter wave hot spot loses a significant percentage of its strength in the short distance from a pole to the ground.

I can’t really blame the marketing folks at AT&T for touting imaginary 5G. It’s what’s hot in the marketplace today and what the public has been primed to expect. But just like the false hype when 4G was first introduced, cellular customers are not on the verge of seeing blazingly fast cellphone service in the places they live and work. This advertising seems to be intended to boost the AT&T brand, but it also might be defensive since other cellular carriers are making similar claims.

Unfortunately, this kind of false advertising plants the notion for politicians and policy-makers that cellular broadband will soon be all we will need. That’s an interesting corporate tactic to take by AT&T which is also building more fiber-to-the-premise right now than anybody else. These false claims seems to be most strongly competing with their own fiber broadband. But as I’ve always said, AT&T wears many hats and I imagine that their own fiber folks are as annoyed by this false advertising as the rest of us in the industry.

A 5G Timeline

Network World recently published their best guess at a timeline for 5G cellular deployment. As happens with all new technologies that make a big public splash, the actual deployment is likely to take a lot longer than what the public expects.

They show the timeline as follows:

  • 2017 – Definition, specification, requirements, technology development and technology field tests
  • 2019/20 – Formal specifications
  • 2021 – Initial production service rollouts
  • 2025 – Critical mass
  • 2030+ – Phase-out of 4G infrastructure begins

There is nothing surprising about this timeline, and in the cellular world we saw something similar with the roll-out of both 3G and 4G and there is no reason to think that 5G will be introduced any faster. There are an incredible number of things that must come to bear before 5G can be widely available.

Just to be clear, this timeline is talking about the use of the 5G standard for cellular service, as opposed to the same 5G terminology that is being used to describe high-speed radio connections used to deliver broadband over short distances. The use of the term 5G is going to be confusing the public for years, until some point where we will need a different name for the two different technologies.

Like with any new technology, it will probably be fifteen years until there is equipment that incorporates the full 5G specification. We are just now finally seeing a full implementation of fully-compliant 4G electronics. This means that early 5G roll-outs will only implement a few of the new features of 5G. Just like with 4G we can then expect successive future 5G roll-outs as new features are introduced and the technology inches forward. We won’t go straight to 5G, but will work our way through 4.1G and 4.2G until we finally get to the full 5G specification.

Here are just a few of the things that have to happen before 5G cellular is widely deployed.

  • Standards have to be completed. Some of the first generation standards will be completed by the end of this year, but that’s not the end of the standards process. There will be continued standards developed over the next few years that look at the practical issues of deploying the technology.
  • Then equipment must be developed that meets the new standards. While many wireless companies are already working on this, it takes a while to go from lab prototype to mass production.
  • True field trials are then needed. In the wireless world we have always seen that there is a big difference between the capabilities that can be tested in a lab versus the real performance that can be had in differing outdoor environments. Real field trials can’t proceed until there are finished deployments that are not prototypes that are then tested in many different environments.
  • Then the cellular companies have to start deploying the equipment into the field. That means not only upgrading the many existing cell towers, but it’s going to mean deploying into smaller neighborhood cell sites. As I’ve written about recently, this means building a lot of new fiber and it means solving the problems of deploying small cell sites in neighborhoods. If we’ve learned anything from the recent attempt by the cell companies to deploy small 4G cell sites it’s that these two issues are going to be a major impediment to 5G deployment. Just paying for all of the needed fiber is a huge hurdle.
  • One of the biggest challenges with a new cellular technology is introducing it into handsets. Handset makers will like the cachet of selling 5G, but the biggest issue with cellphones is battery power and it’s going to be costly and inefficient to deploy the more complicated 5G big-MIMO antennae in handsets. That’s going to make the first generation of 5G handsets expensive. This is always the catch-22 of a new cellular technology – cellphone makers don’t want to commit to making big volumes of more-expensive phones until customer can actually use the new technology, and the cellphone makers won’t deploy too much of the 5G technology until there are enough handsets in the world to use it. I’ve seen some speculation that this impasse could put a real hitch in 5G cellular deployment.

To a large degree the cellular industry it its own worst enemy. They have talked about 5G as the savior of all of our bandwidth problems, when we know that’s not true. Let’s not forget that when 4G was introduced fifteen years ago that the industry touted ubiquitous 100 Mbps cellphone connections – something that is still far above our capabilities today. One thing not shown on the timeline is the time when we finally get actual 5G capabilities on our cellphones. It’s likely to be 15 years from now, at about the time when we have shifted our attention to 6G.

Is our Future Mobile Wireless?

I had a conversation last week with somebody who firmly believes that our broadband future is going to be 100% mobile wireless. He works for a big national software company that you would recognize and he says the company believes that the future of broadband will be wireless and they are migrating all of their software applications to work on cellphones. If you have been reading my blog you know I take almost the opposite view, but there are strong proponents of a wireless future, and it’s a topic worth continually revisiting.

Certainly we are doing more and more things by cellphone. But I think those that view future broadband as mobile are concentrating on faster mobile data speeds but are ignoring the underlying overall data capacity of cellular networks. I still think that our future is going to become even more reliant on fiber in order to handle the big volumes of bandwidth we will all need. This doesn’t mean that I don’t love cellphone data – but I think it’s a complement for landline broadband and not an equivalent substitute. Cellphone networks have major limitations and they are not going to be able to keep up with our need for bandwidth capacity. Even today the vast majority of cellphone data is handed off to landline networks through WiFi. And in my mind that just makes a cellphone into another terminal on your landline network.

Almost everybody understands the difference in quality between using your cellphone in your home using WiFi versus doing the same tasks using only the cellular network. I largely use my cellphone for reading news articles. And while this is a lot lighter application than watching video, I find that I usually have problems opening articles on the web when I’m out of the house. Today’s 4G speeds are still pretty poor and the national average download speed is reported to be just over 7 Mbps.

I think all of the folks who think cellphones are the future are counting on 5G to make a huge difference. But as I’ve written many times, it will be at least a decade before we see a mature 5G cellular network – and even then the speeds are not likely to be hugely faster than the 4G specification today. 5G is really intended to increase the stability of broadband connections (less dropped calls) and the number of connections (able to connect to a lot of IoT devices). The 5G specifications are not even shooting for at a huge speed increase, with the specification calling for 100 Mbps download cellular speeds, which translates into an average of perhaps 50 Mbps connections for all of the customers within a cell site. Interestingly, that’s the same target speed of the 4G specification.

And those greater future speeds sounds great. Since a cellphone connection by definition is for one user, a faster speed means that a cellular connection will support a 4K video stream eventually. But what this argument ignores is that a home a decade from now is going to be packed with devices wanting to make simultaneous connections to the Internet. It is the accumulated volume of usage from all of those devices that is going to add up to huge broadband demand for homes.

Already today homes are packed with broadband hungry devices. We have smart TVs, cellphones, laptops, desktops and tablets all wanting to connect to the network. We have other bandwidth hungry applications like gaming boxes and surveillance cameras. More and more of us are cutting the cord and watching video online. And then there are going to piles of new devices with smaller broadband demands, but which in total will add up to significant bandwidth. Further, a lot of applications we use are now in the cloud. My home uses a lot of bandwidth every day just backing up my data files, connecting to software in the cloud, making VoIP calls, and automatically updating software and apps.

I’ve touted a statistic many times that you might be tired of hearing, but I think it’s at the heart of the matter. The amount of bandwidth used by homes has been doubling every three years since 1980, and there is no end in sight to that trend. Already today a 4G connection is inadequate to support the average home. If you don’t think that’s true, talk to the homes now using AT&T’s fixed LTE connections that deliver 10 Mbps. That kind of speed is not adequate today to provide enough bandwidth to use the many broadband services I discussed above. Cellular connections are already too slow today to provide a reasonable home broadband, even as AT&T is planning to foist these connections on millions of rural homes.

There is no reason to think that 5G will be able top satisfy the total broadband needs of a home. The only way it might do that is if we end up in a world where we have to buy a small cellular subscription for every device in our home – I know I would prefer to instead connect all of my devices to WiFi to avoid such fees. Yes, 5G will be faster, but a dozen years from now when 5G is finally a mature cellular technology, homes will need a lot more bandwidth and a 5G connections then will feel just as inadequate then as 4G feels today.

Unless we get to a future point where the electronics get so cheap that there will be a ‘cell site’ for every few homes, then it’s hard to figure that cellular can ever be a true substitute for landline broadband. And even if such a technology develops you still have to ask if it would make any sense to deploy. Those small cell sites are largely going to have to be fiber fed to deliver the needed bandwidth and backhaul. And in that case small cell sites might not be any cheaper than fiber directly to the premise, especially when considering the lifecycle costs of the cell site electronics. Even if we end up with that kind of network – it’s would not really be a cellular network as much as it would be using wireless loops as the last few feet of a landline network – something that for years we have called fiber-to-the-curb. Such a network would still require us to build fiber almost everywhere.

Standards for 5G

itu_logo_743395401Despite all of the hype that 5G is right around the corner, it’s important to remember that there is not yet a complete standard for the new technology.

The industry just took a big step on February 22 when the ITU released a draft of what it hopes is the final specification for 5G. The document is heavy in engineering detail and is not written for the layman. You will see that the draft talks about a specification for ‘IMT-2020’ which is the official name of 5G. The goal is for this draft to be accepted at a meeting of the ITU-R Study Group in November.

This latest version of the standard defines 13 metrics that are the ultimate goals for 5G. A full 5G deployment would include all of these metrics. What we know that we will see is commercial deployments from vendors claiming to have 5G, but which will actually meet only some parts of a few of these metrics. We saw this before with 4G, and the recent deployment of LTE-U is the first 4G product that actually meets most of the original 4G standard. We probably won’t see a cellular deployment that meets any of the 13 5G metrics until at least 2020, and it might be five to seven more years after that until fully compliant 5G cellular is deployed.

The metric that is probably the most interesting is the one that establishes the goal for cellular speeds. The goals of the standard are 100 Mbps download and 50 Mbps upload. Hopefully this puts to bed the exaggerated press articles that keep talking about gigabit cellphones. And even should the technology meet these target speeds, in real life deployment the average user is probably only going to receive half those speeds due to the fact that cellular speeds decrease rapidly with distance from a cell tower. Somebody standing right next to a cell tower might get 100 Mbps, but even as close as a mile away the speeds will be considerably less.

Interestingly, these speed goals are not much faster than is being realized by LTE-U today. But the new 5G standard should provide for more stable and guaranteed data connections. The standard is for a 5G cell site to be able to connect to up to 1 million devices per square kilometer (a little more than a third of a square mile). This, plus several other metrics, ought to result in stable 5G cellular connections – which is quite different than what we are used to with 4G connections. The real goal of the 5G standard is to provide connections to piles of IoT devices.

The other big improvement over 4G are the expectations for latency. Today’s 4G connections have data latencies as high as 20 ms, which accounts for most problems in loading web pages or watching video on cellphones. The new standard is 4 ms latency, which would improve cellular latency to around the same level that we see today on fiber connections. The new 5G standard for handing off calls between adjoining cell sites is 0 ms, or zero delay.

The standard increases the demand potential capacity of cell sites and provides a goal for the ability of a cell site to process peak data rates of 20 Gbps down and 10 Gbps up. Of course, that means bringing a lot more bandwidth to cell towers and only extremely busy urban towers will ever need that much capacity. Today the majority of fiber-fed cell towers are fed with 1 GB backbones that are used to satisfy upload and download combined. We are seeing cellular carriers inquiring about 10 GB backbones, and we need a lot more growth to meet the capacity built into the standard.

There are a number of other standards. Included is a standard requiring greater energy efficiency, which ought to help save on handset batteries – the new standard allows for handsets to go to ‘sleep’ when not in use. There is a standard for peak spectral efficiency which would enable 5G to much better utilize existing spectrum. There are also specifications for mobility that extend the goal to be able to work with vehicles going as fast as 500 kilometers per hour – meaning high speed trains.

Altogether the 5G standard improves almost every aspect of cellular technology. It calls for more robust cell sites, improved quality of the data connections to devices, lower energy requirements and more efficient hand-offs. But interestingly, contrary to the industry hype, it does not call for gigantic increases of cellular handset data speeds compared to a fully-compliant 4G network. The real improvements from 5G are to make sure that people can get connections at busy cell sites while also providing for huge numbers of connections to smart cars and IoT devices. A 5G connection is going to feel faster because you ought to almost always be able to make a 5G connection, even in busy locations, and that the connection will have low latency and be stable, even in moving vehicles. It will be a noticeable improvement.

Looking Closer at 5G

SONY DSCCisco recently released a white paper titled Cisco 5G Vision Series: Laying the Foundation for New Technologies, Use Cases, and Business Models that lays out their vision of how the cellular industry can migrate from 4G to 5G. It’s a highly technical read and provides insight on how 5G might work and when we might see it in use.

As the white paper points out, the specific goals of 5G are still in the process of being developed. Both 4G and 5G are basically a set of detailed standards used to make sure devices can work on any network meeting the standards. Something that very few people realize is that almost none of the supposed 4G networks in this country actually meet the 4G standards. We are just now seeing the deployment around the world of the first technologies – LTE-Advanced and WIMAX 16m – that meet the original 4G standards. It’s been typical for cellular providers to claim to have 4G when they’ve only met some tiny portion of the standard.

And so, long before we see an actual 5G deployment we are first going to see the deployment of LTE-Advanced followed by generations of improvements that are best described as pre-5G (just as most of what we have today is pre-4G). This evolution means that we should expect incremental improvements in the cellular networks, not a big swooping overhaul.

The paper makes a very clear distinction between indoor 5G and outdoor 5G (which is cellular service). Cisco says that already today that 80% of cellphone usage is done indoors, mostly using WiFi. They envision that in places with a lot of people, like stadiums, shopping centers or large business buildings, that there will be a migration from WiFi to millimeter wave spectrum using the 5G standard. This very well could ultimately result in gigabit speeds on devices with the right antennas to receive that signal.

But these very fast indoor speeds are going to be limited to those places where it’s economically feasible to deploy multiple small cells – and places that have good fiber backhaul. That’s going to mean places with lots of demand and the willingness to pay for such deployments. So you might see fast speeds inside wireless in hospitals, but you are not going to see gigabit speeds while waiting for your car to be repaired or while sitting in the dentist waiting room. And most importantly, you are not going to see gigabit speeds using millimeter wave spectrum outside. All of the early news articles talking about having outdoor gigabit cellular speeds were way off base. This misunderstanding is easy to understand since the press releases from cellular companies have been nebulous and misleading.

So what can be expected outdoors on our cell phones? Cisco says that the ultimate goal of 5G is to be able to deliver 50 Mbps speeds everywhere. At the same time, the 5G standards have the goal of being able to handle a lot more connections at a given cell site. That goal will mean better reception at football games, but it also means a lot more connections will be available to connect to smart cars or Internet of Things devices.

But don’t expect much faster cellular speeds for quite some time. Remember that the goal of 4G was to deliver about 15 Mbps speeds everywhere. And yet today, the average LTE connection in the US is at about half of that speed. The relatively slow speeds of today’s LTE are due to a number of different reasons. First, is the fact that most cell sites are still running pre-4G technology. The willingness of the cellular companies to buy sufficient bandwidth backhaul at cell sites is also a big contributor. I’ve seen in the press that both Verizon and AT&T are looking for ways to reduce backhaul costs – that’s thought to be the major motivation for Verizon to buy XO Communications. Another major issue is that existing cell sites are too far apart to deliver fast data speeds, and it will require a massive deployment of small cell sites (and the accompanying fiber backhaul) to fix the spacing problem.

So long before we see 50 Mbps cellular speeds we will migrate through several generations of incremental improvements in the cellular networks. We are just now seeing the deployment of LTE-Advanced which will finally bring 4G speeds. After that, Cisco has identified what looks to be at least three or four steps of improvements that we will see before we achieve actual 5G cellular.

How long might all of this take? The industry is scheduled to finalize the 5G standards by 2020, and perhaps a little sooner. It looks like there will be a faster push to find millimeter wave solutions for indoor 5G, so we might see those technologies coming first. But it has taken us a decade since the large cellular companies announced deployment of 4G cellular until we are finally starting to see networks that meet that standard. I can’t imagine that the 5G migration will go any faster. And even when 5G gets here, it’s going to hit urban areas long before it hits rural areas. One doesn’t have to drive too far into the country today to find places that are still operating at 3G.

Upgrading to 5G in steps will be expensive for the cellular providers and they are not likely to implement changes too quickly. We will likely see a series of incremental improvements, like they have been doing for many years. So it would not be surprising to be at least until 2030 until there is a cellular system in place that fully meets the 5G standard. Of course, long before then the marketing departments of the wireless providers will tell us that 5G is here – and when they do, everybody looking for blazingly fast cellphone speeds are going to be disappointed.

Issues Facing Cellular Networks

Cell-TowerMost networks today are under stress due to growing broadband traffic. The networks that are easily the most stressed are cellular networks and I think that there can be lessons learned in looking how mobile providers are struggling to keep up with demand. Consider the following current issues faced by cellular network owners:

Traffic Volume Growth. Around the world cellular networks are seeing between 60% to 120% annual growth in data volumes. The problem with that kind of growth is that as soon as any upgrade is made to a part of the network it is consumed by the growth. This kind of growth means constant choke points in the network and problems encountered by customers.

The large cellular companies like Verizon and AT&T are handling this with big annual capital budgets for network improvements. But they will be the first to tell you that even with those expenditures they are only putting band-aids on the problem and are not able to get ahead of the demand curve.

WiFi Offload Not Effective. For years cellular networks have talked about offloading data to WiFi. But the industry estimates are that only between 5% and 15% of data through cellphones is being handled by WiFi. This figure does not include usage in homes and offices where the phone user elects to use their own local network, but rather is the traffic that is offloaded when users are outside of their base environment. Finding ways to increasing WiFi offload would lower the pressure on mobile networks.

Traffic has Moved Indoors. An astounding 75% of mobile network traffic originates from inside buildings. Historically mobile traffic came predominantly from automobiles and people outside, but the move indoors looks like a permanent new phenomenon driven by video and data usage.

The biggest impact of this shift is that most cellular networks were designed and the towers spaced for outdoor customers and so the towers and radios are in the wrong places to best serve where the volume is greatest today. This trend is the number one driver of micro cell sites that are aimed at relieving congestion for specific locations.

Network Problems Can be Extremely Local. The vagaries of wireless delivery mean that there can be network congestion at a location but no network issues as close as 50 yards away. This makes it very hard to diagnose and fix network issues. Problems can pop up and disappear quickly. A few more large data users than normal can temporarily cripple a given cell site.

Network owners are investigating technologies that will allow customers to pick up a more distant cell site when their closest one is full. Wireless networks have always allowed for this but it’s never worked very well in practice. The carriers are looking for a more dynamic process that will find he best way to serve each customer quickly in real time.

Networks are Operating too Many Technologies. It’s not unusual to find a given cell site operating several versions of 3G and 4G and sometimes still even 2G. The average cell site carries 2.2 different technologies, provided by 1.3 different vendors.

Cellular operators are working quickly towards software defined networks that will allow them to upgrade huge numbers of cell sites to a new version of software at the same time. They are also working to separate voice and data to different frequencies making it easier to handle each separately. Finally, the large cellular carriers are looking to develop and manufacture their own custom equipment to cut down on the number of vendors.

Still Too Many Failures. There are still a lot of dropped voice calls, and 80% of them are caused by mobility failures, meaning a failure of the network to handle a customer on the move. 50% of dropped data sessions are due to capacity issues.

Cellular providers are looking for the capacity to more dynamically assign radio resources on the fly at different times of the day. It’s been shown that there are software techniques that can optimize the local network and can reduce failures by as much as 25%.

The 5G Hype

Cell-TowerBoth AT&T and Verizon have had recent press releases about how they are currently testing 5G cellular data technology, and touting how wonderful it’s going to be. The AT&T Press release on 5G included the following statements:

Technologies such as millimeter waves, network function virtualization (NFV), and software-defined networking (SDN) will be among the key ingredients for future 5G experiences. AT&T Labs has been working on these technologies for years and has filed dozens of patents connected with them. . . . We expect 5G to deliver speeds 10-100 times faster than today’s average 4G LTE connections. Customers will see speeds measured in gigabits per second, not megabits.

AT&T went on to say that they are testing the technology now and plan to start applying it in a few applications this year in Austin, TX.

This all sounds great, but what are the real facts about 5G? Consider some of the following:

Let’s start with the standard for 5G. It has not yet been developed and is expected to be developed by 2018. The Next Generation Mobile Network Alliance (the group that will be developing the standard) states that the standard is going to be aimed at enabling the following:

  • Data rates of several tens of megabits per second should be supported for tens of thousands of users;
  • 1 gigabit per second can be offered simultaneously to workers on the same office floor;
  • Several hundreds of thousands of simultaneous connections to be supported for massive sensor deployments

How does this stack up against AT&T’s claims? First, let’s talk about how 4G does today. According to OpenSignal (who studies the speeds from millions of cellular connections), the average LTE download speeds in the 3rd quarter of last year for the major US carriers was 6 Mbps for Sprint, 8 Mbps for AT&T, and 12 Mbps for both Verizon and T-Mobile.

The standard is going to be aimed to improve average speeds for regular outdoor usage to ‘several tens of megabits per second’ which means speeds of maybe 30 Mbps. That is a great data speed on a cellphone, but it is not 10 to 100 times faster than today’s 4G speeds, but instead a nice incremental bump upward.

Where the hype comes from is the part of the standard that talks about delivering speeds within an office. With 5G that is going to be a very different application, and that very well might achieve gigabit speeds. This is where the millimeter waves come into play. As it turns out, AT&T and Verizon are talking about two totally different technologies and applications, but are purposefully making people think there will be gigabit cellular data everywhere.

The 5G standard is going to allow for the combination of multiple very high frequencies to be used together to create a very high bandwidth data path of a gigabit or more. But there are characteristics of millimeter wavelengths that limit this to indoor usage inside the home or office. For one, these frequencies won’t pass through hardly anything and are killed by walls, curtains, and to some extent even clear windows. And the signal from these frequencies can only carry large bandwidth a very short distance – at the highest bandwidth perhaps sixty feet. This technology is really going to be a competitor to WiFi but using cellular frequencies and standards. It will allow the fast transfer of data within a room or an office and would provide a wireless way to transmit something like Google’s gigabit broadband around an office without wires.

But these millimeter waves are not going to bring the same benefits outdoors that they can do indoors. There certainly can be places where somebody could get much faster speeds from 5G outdoor – if they are close to a tower and there are not many other users. But these much faster speeds are not going to work, for example, for somebody in a moving car. The use of multiple antennas for multiple high frequencies is going to require an intricate and complicated antenna array at both the transmitter and the receiver. But in any case the distance limitations and the poor penetration ability of millimeter frequencies means this application will never be of much use for widespread outdoor cellphone coverage.

So 5G might mean that you will be able to get really fast speeds inside your home, at a convention center or maybe a hotel, assuming that those places have a very fast internet backbone connection. But the upgrade to what you think of as cellular data is going to be a couple-fold increase in data speeds for the average user. And even that is going to mean slightly smaller coverage circles from a given cell tower than 4G.

The problem with this kind of hype is that it convinces non-technical people that we don’t need to invest in fiber because gigabit cellular service is coming very soon. And nothing could be further from the truth. There will someday be gigabit speeds, but just not in the way that people are hoping for. And both big companies make this sound like it’s right around the corner. There is no doubt that the positive press over this are is great for AT&T and Verizon. But don’t buy the hype – because they are not promising what people think they are hearing.

Our Lagging 4G Networks

Cell-TowerI have to scratch my head when I read about people who rave about the 4G data speeds they get. First, I travel all over the country and I have yet to see a 4G data speed above 20 Mbps. And yet I’ve seen claims in various online forums for speeds as high as 60 Mbps. I’ve been in a number of major cities in the last six months and have not once seen speeds that I would consider fast.

Second, a report just came out from OpenSignal, a company that provides an app that maps cellular coverage. They collected data recently from 325,000 users around the world and used that data to compare the 4G networks in 140 different countries. Their data showed that the US has the 14th slowest 4G of all these countries at an average paltry speed of 10 Mbps.

Hungary, Denmark, South Korea, Romania, Singapore, and New Zealand have the fastest 4G, all with average speeds of above 25 Mbps, with New Zealand seeing an average speed of 36 Mbps download.

I often run speed tests, but the real way to test 4G speeds is by trying to open web pages I often use at home. I know it’s generally far more efficient to use an app rather than the mobile web, but I open web pages just to see how fast coverage is. It’s well known that speed test results can be rigged by your carrier who knows you are using a speed test site. What I generally find is that web pages that leap onto my screen at home seem to take forever to load on my cellphone, and sometimes they never load.

Why does this matter? I think it matters because there are tons of industry pundits who opine that our broadband future is wireless and that we don’t need to be investing in fiber. They say that wireless is going to get so fast that nobody will feel the need for a landline based internet connection. For a whole long list of reasons I think that argument is totally bosh. Consider the following:

  • Cellular data speeds drop quickly with distance from the cell tower. Today cell phone towers are not situated for data coverage and were built to handle voice traffic. A cell tower can complete a voice call at a much greater distance from the tower than it can make a strong data connection.
  • We could always build more towers to bring transmitters closer to people. But for those new towers to work they are going to have to be fiber fed, something that very few companies are willing to invest in.
  • Cell phone signals don’t penetrate structures very well. I recently visited my dentist. In the parking lot I was easily able to read news articles on Flipboard. I then walked into the waiting room, which has big windows to the outside world, but the ability to read articles slowed down a lot. Then when I was taken back to an interior room that was only one room further from the outside, I couldn’t even get the app to open. This is not an unusual experience and I see it often.
  • Cell sites can only handle a limited number of customers and they get overwhelmed and degrade if they get more demand than optimum. And the more bandwidth that is delivered, the easier it is for a cell site to reach capacity.
  • The various swaths of spectrum used for cellular data each have their own unique limitations. In many cases the spectrum is carved into somewhat small channels (which was done before we conceived using the spectrum for data) and it’s very hard to cobble together a large wireless data path. It generally means linking several frequencies to a given customer data path, which is both complicated and somewhat taxing on a cellphone.
  • Data caps, data caps, data caps. Let’s face it, as long as the cellphone companies want to charge $10 per downloaded gigabit then they cannot be a serious contender for anybody’s real life data usage. I estimate that my household downloads at least 500 gigabits per month at home and I don’t think we are unusual. If I was paying cellphone data rates that would cost me an astounding $5,000 per month. Even should they cut their rates by 90% this would still cost an eye-popping $500 per month. As long as cellphone data rates are 100 times higher than landline rates they are something you use to casually browse the news, not as a real internet connection.