5G in China

There is an interesting recent article in the English version of a South Korean newspaper, the ChosunILBO, that talks about 5G in China. According to the article, the Chinese 5G rollout is an expensive bust.

There are a number of interesting facts disclosed about the Chinese 5G roll-out. First, it’s clear that the roll-out is using millimeter wave spectrum. The article says that the 5G towers in the Chinese networks are being installed about 200 meters apart (600 feet) since the signal from each transmitter travels between 100 and 300 meters. That’s consistent with millimeter wave hot spots being deployed in downtown cities by Verizon.

It takes a huge number of millimeter wave cell sites to cover a city and the article says that by the end of June 2020 that the Chinese had installed 410,000 cell sites. The article estimates that to get the same coverage as today’s 4G that the network would eventually need over 10 million cell sites. The article quotes Xiang Ligang, the director-general of the Information Consumption Alliance, a Chinese telecom industry association, who said the plans are to build one million new cell sites in each of the next three years.

The 5G coverage isn’t seeing wide acceptance. The article cites a recent Chinese survey where over 73% of the public says there is no need to buy 5G phones. This matched the findings from another survey that also said the public saw no need for 5G.

One of the more interesting things cited in the article is that the 5G cell sites use a lot of energy and that starting in August, China Unicom has taken to shutting the cell sites down from 9 PM until 9 AM daily to save on electricity costs. They say each cell site is using triple the power of a 4G cell site, and there are a lot of sites to power. The new 5G specifications include a provision to significantly reduce power consumption for 5G cell sites, but in the early days of deployment, it looks like this has gone in the wrong direction.

The article concludes that the Chinese 5G experiment might end up as an economic bust. What’s interesting about this article is that a lot of the same things can be said about 5G in South Korea. It’s been reported that South Korea has the biggest percentage penetration of 5G handsets, but that the public has largely been panning the service.

None of this is surprising. The 5G deployment using millimeter wave spectrum is an outdoor technology and can only be brought indoors by installing numerous 5G transmitters inside a building since the spectrum won’t pass through walls. There is no doubt that the millimeter wave signals are fast, but as has been demonstrated here, the reception of signal is squirrely. Apparently, bandwidth comes and goes by a simple twist of the hand and the user’s body can block the millimeter wave signals. Add that to the inability to continue with a connection when walking into a building or around the corner of a building, and the millimeter wave product doesn’t sound particularly user friendly.

The outdoor product possibly makes sense in places where people stay and work outside, such as public markets. But it’s not an inviting technology for people who are only outside to go between buildings or to commute.

There are no indications that Verizon intends to deploy the product widely in the US, or at least not in the same manner that would cover a city in cell sites every 600 feet.

There has been a huge amount of hype in this country about being in a race with the Chinese over the deployment of 5G. But after seeing articles like this, perhaps our best strategy is to lay back and wait until 5G equipment gets cheaper and until the new 5G cell sites are made energy efficient. For now, it doesn’t sound like a race we want to win.

5G and Rural America

FCC Chairman Ajit Pai recently told the crowd at CES that 5G would be a huge benefit to rural America and would help to close the rural broadband divide. I have to imagine he’s saying this to keep rural legislators on board to support that FCC’s emphasis on promoting 5G. I’ve thought hard about the topic and I have a hard time seeing how 5G will make much difference in rural America – particularly with broadband.

There is more than one use of 5G, and I’ve thought through each one of them. Let me start with 5G cellular service. The major benefits of 5G cellular are that a cell site will be able to handle up to 100,000 simultaneous connection per cell site. 5G also promises slightly faster cellular data speeds. The specification calls for speeds up to 100 Mbps with the normal cellular frequencies – which happens to also have been the specification for 4G, although it was never realized.

I can’t picture a scenario where a rural cell site might need 100,000 simultaneous connections within a circle of a few miles. There aren’t many urban places that need that many connections today other than stadiums and other crowded locations where a lot of people want connectivity at the same time. I’ve heard farm sensors mentioned as a reason for needing 5G, but I don’t buy it. The normal crop sensor might dribble out tiny amounts of data a few times per day. These sensors cost close to $1,000 today, but even if they somehow get reduced to a cost of pennies it’s hard to imagine a situation where any given rural cell site is going to need to more capacity than is available with 4G.

It’s great if rural cell sites get upgraded, but there can’t be many rural cell sites that are overloaded enough to demand 5G. There is also the economics. It’s hard to imagine the cellular carriers being willing to invest in a rural cell site that might support only a few farmers – and it’s hard to think the farmers are willing to pay enough to justify their own cell site

There has also been talk of lower frequencies benefitting rural America, and there is some validity to that. For example, T-Mobile’s 600 MHz frequency travels farther and penetrates obstacles better than higher frequencies. Using this frequency might extend good cellular data coverage as much as an extra mile and might support voice for several additional miles from a cell site. However, low frequencies don’t require 5G to operate. There is nothing stopping these carriers from introducing low frequencies with 4G (and in fact, that’s what they have done in the first-generation cellphones capable of using the lower frequencies). The cellular carriers are loudly claiming that their introduction of new frequencies is the same thing as 5G – it’s not.

5G can also be used to provide faster data using millimeter wave spectrum. The big carriers are all deploying 5G hot spots with millimeter wave technology in dense urban centers. This technology broadcasts super-fast broadband for up to 1,000 feet.  The spectrum is also super-squirrely in that it doesn’t pass through anything, even a pane of glass. Try as I might, I can’t find a profitable application for this technology in suburbs, let alone rural places. If a farmer wants fast broadband in the barnyard I suspect we’re only a few years away from people being able to buy a 5G/WiFi 6 hot spot that could satisfy this purpose without paying a monthly fee to a cellular company.

Finally, 5G can be used to provide gigabit wireless loops from a fiber network. This is the technology trialed by Verizon in a few cities like Sacramento. In that trial, speeds were about 300 Mbps, but there are no reason speeds can’t climb to a gigabit. For this technology to work there has to be a transmitter on fiber within 1,000 feet of a customer. It seems unlikely to me that somebody spending the money to get fiber close to farms would use electronics for the last few hundred feet instead of a fiber drop. The electronics are always going to have problems and require truck rolls, and the electronics will likely have to be replaced at least once per decade. The small telcos and electric coops I know would scoff at the idea of adding another set of electronics into a rural fiber network.

I expect some of the 5G benefits to find uses in larger county seats – but those towns have the same characteristics as suburbia. It’s hard to think that rural America outside of county seats will ever need 5G.

I’m at a total loss of why Chairman Pai and many politicians keep extolling the virtues of rural 5G. I have no doubt that rural cell sites will be updated to 5G over time, but the carriers will be in no hurry to do so. It’s hard to find situations in rural America that demand a 5G solution that can’t be done with 4G – and it’s even harder to justify the cost of 5G upgrades that benefit only a few customers. I can’t find a business case, or even an engineering case for pushing 5G into rural America. I most definitely can’t foresee a 5G application that will solve the rural broadband divide.

 

FCC Approves New 5G Spectrum

FCC_New_LogoIn what is already being called the 5G Order, in Docket FCC 16-89 the FCC just released a lot of new spectrum. Quoted directly from the FCC Order the new spectrum is as follows:

Specifically, the rules create a new Upper Microwave Flexible Use service in the 28 GHz (27.5-28.35 GHz), 37 GHz (37-38.6 GHz), and 39 GHz (38.6-40 GHz) bands, and an unlicensed band at 64-71 GHz.

  • Licensed use in the 28 GHz, 37 GHz and 39 GHz bands: Makes available 3.85 GHz of licensed, flexible use spectrum, which is more than four times the amount of flexible use spectrum the FCC has licensed to date.
    • Provides consistent block sizes (200 MHz), license areas (Partial Economic Areas), technical rules, and operability across the exclusively licensed portion of the 37 GHz band and the 39 GHz band to make 2.4 GHz of spectrum available.
    • Provides two 425 MHz blocks for the 28 GHz band on a county basis and operability across the band.
  • Unlicensed use in the 64-71 GHz band: Makes available 7 GHz of unlicensed spectrum which, when combined with the existing high-band unlicensed spectrum (57-64 GHz), doubles the amount of high-band unlicensed spectrum to 14 GHz of contiguous unlicensed spectrum (57-71 GHz). These 14 GHz will be 15 times as much as all unlicensed Wi-Fi spectrum in lower bands.

The U.S. is the first country to authorize specific use of this much spectrum in these upper bands, which have commonly been referred to as millimeter wave spectrum. And the FCC isn’t yet finished. Along with the Order, the FCC issued a Further Notice for Proposed Rulemaking to look at how it should deal with other blocks of spectrum, including existing space in the 24-25 GHz, 32 GHz, 42 GHz, 48 GHz, 51 GHz, 70 GHz, and 80 GHz. The FCC also asked for comments on how it might provide access to spectrum above 95 GHz.

The FCC hopes that opening up this spectrum will result in a lot of new wireless applications. Today there are two planned uses for the millimeter wave spectrum. The cellular 5G standard talks about using this spectrum on a broadcast basis to deliver high bandwidth for short distances. That most likely means use as a way to deliver big bandwidth wirelessly within a room or office.

There is also an application today for using these frequencies for point-to-point microwaves. These radios can deliver about 2 gigabits on a point-to-point basis and can act as a fiber replacement where the economics make sense. But these frequencies are largely killed by heavy rain and they need pure line-of-site, meaning nothing between the transmitter and the receiver. Still, there are hopes that in rural areas this could be a replacement for building expensive fiber for just a few customers, or as a way to reach remote locations.

The FCC is hoping that releasing such large blocks of spectrum will result in a burst of research and development, much like what happened when they first released WiFi. At that time the FCC first created WiFi spectrum blocks there were only a few applications envisioned, but engineers and entrepreneurs have since developed a huge range of WiFi applications far beyond what the FCC first envisioned.

The FCC is adopting flexible regulatory rules for the new spectrum. Licensees will be able to get a 10-year license either as a common carrier, as a non-common carrier or for private internal communications. They are expecting to issue numerous licenses per area and don’t expect a lot of interference issues due to the short-distance nature of the propagation for these spectrums. A lot of the specific details will need to be generated by the FCC Wireless Bureau.