28 GHz is the most popular band of millimetre wave high-frequency spectrum. It was generally little used in the U.S. but now Verizon plans to pass 30 million homes in the first phase of the buildout. Europe chose 26 GHz because satellites were using 28 GHz. There is little gear available other than for 26-30 GHz. Verizon controls 800 MHz of the band in the U.S.

39 GHz, some AT&T controlled, requires 50% more antennas than 28 GHz and is not as popular. AT&T cutbacks in mmWave mean 39 GHz mostly will be on the shelf for years.

60 GHz, shared in the U.S., was developed by Intel as WiGig but didn't find a market. CCS, Facebook, Qualcomm, and others are reviving it, especially for backhaul. The FCC has allocated 14 GHz. With enough very small antennas, performance looks good.

Other bands above 15 GHz lack equipment or supporters, so are years away. The U.S. FCC is about to auction 24 GHz.

Low and mid-band

3.3 GHz to 4.2 GHz is the emerging new band, with enough available spectrum for several companies to expect the ideal 100 MHz.

Over $10 billion of auctions are completed or coming soon, including Korea, Spain, and the UK. Until Massive MIMO reached production in 2016, these bands didn't have enough reach for most practical purposes. With MM, they have become prime, although phones are few. 

2.5 GHz to 3.0 GHz has seen limited use until recently but now is the core of Sprint's network buildout. Performance is much improved with Massive MIMO.

2.3 GHz is also now coming into wider use, including at AT&T.

1.8 GHz to 2.1 GHz have been primary bands in 3G & 4G. They will be re-farmed for 5G as available. 4x4 MIMO is very effective, but Massive MIMO less so. As frequencies get lower, antennas get larger and sometimes impractical. These bands are designated FDD, which severely limits performance.

600 MHz to 1 GHz are ideal 4G bands with excellent reach and indoor coverage. Add NR software, and these frequencies become "5G," The antennas are larger and FDD does not work well for Massive MIMO.

Why many engineers consider only high frequencies 5G  

Until late 2017 only mmWave was considered 5G, including in the ITU IMT-2020 definition. Theoretical peak speeds are up to 20 gigabits, although networks like Verizon top out at 5-7 gigabits. The speed is due to the large amount of spectrum available. 5G is designed to use 400 MHz in high bands; Verizon has 800 MHz.

About a year ago, the marketing people took over. They wanted to call everything 5G and pushed through the 3GPP standards group a definition of 5G that included all bands as long as a modest software tweak (NR) was included. Suddenly, even the lowest frequencies in active use - T-Mobile's 600 MHz in the U.S. - could be called "5G." The "NR" software adds only a little performance compared to 4G using the same frequency and antennas. These bands are best considered 4G-like. Whether called 4G or 5G, these bands use a maximum of 100 MHz and peak at ~ 2 gigabits.

Fortunately, 4G reaches well into the hundreds of megabits to typical users and has enough capacity to meet projected needs well into next decade.

 

dave askOn Oct 1, Verizon will turn on the first $20B 5G mmWave network, soon offering a gigabit or close to 30M homes. The estimates you hear about 5G costs are wildly exaggerated. Verizon is building the most advanced wireless network while keeping capex at around 15%.

The Koreans, Chinese, and almost all Europeans are not doing mmWave in favor of mid-band "5G," with 4G-like performance. Massive MIMO in either 4G or "5G" can increase capacity 4X to 10X, including putting 2.3 GHz to 4.2 GHz to use. Cisco & others see traffic growth slowing to 30%/year or less. Verizon sees cost/bit dropping 40% per year. I infer overcapacity almost everywhere.  

The predicted massive small cell builds are a pipe dream for vendors for at least five years. Verizon expects to reach a quarter of the U.S. without adding additional small cells. 

In the works: Enrique Blanco and Telefonica's possible mmWave disruption of Germany; Believe it or don't: 5G is cheap because 65% of most cities can be covered by upgrading existing cells; Verizon is ripping out and replacing 200,000 pieces of gear expecting to save half. 

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 5G Why Verizon thinks differently and what to do about it is a new report I wrote for STL Partners and their clients.

STL Partners, a British consulting outfit I respect, commissioned me to ask why. That report is now out. If you're a client, download it here. If not, and corporate priced research is interesting to you, ask me to introduce you to one of the principals.

It was fascinating work because the answers aren't obvious. Lowell McAdam's company is spending $20B to cover 30M+ homes in the first stage. The progress in low & mid-band, both "4G" and "5G," has been remarkable. In most territories, millimeter wave will not be necessary to meet expected demand.

McAdam sees a little further. mmWave has 3-4X the capacity of low and mid-band. He sees an enormous marketing advantage: unlimited services, even less congestion, reputation as the best network. Verizon testing found mmWave rate/reach was twice what had been estimated. All prior cost estimates need revision.

My take: even if mmWave doesn't fit in your current budget, telcos should expand trials and training to be ready as things change. The new cost estimates may be low enough to change your mind.