US 5G is largely based on reusing old 4G spectrum. We cover the nation with low-band 5G that has performance similar to 4G, and have little spots of Verizon's super-speedy ultra-wideband, also known as millimeter-wave. Only one of our carriers, T-Mobile, is currently building a mid-band network that promises differentiated performance across whole cities.
That's resulted in the US winding up at the bottom of 5G speed league tables, according to studies from OpenSignal and others.
In the rest of the world, though, the 5G situation is quite different, according to presenters at Mobile World Congress Shanghai's 5G Spectrum and Policy Forum. There, mid-band spectrum between 2 and 7GHz rules—especially the C-band, which just got auctioned off in the US for more than $80 billion. We're waiting for the FCC to announce the winners of that auction.
The countries that rank at the top of 5G performance are those with dedicated allotments of around 100MHz of mid-band airwaves per carrier, Huawei's Tide Xu said at MWC Shanghai. "If spectrum hasn't been allocated decently, operators need five times the investment to develop it," he said.
"If there are three or four operators in a country who can get those high bandwidths in a continuous way, it can bring many times [investment as revenue,]" he said.
The US may be behind the leaders, but some Asian countries haven't even started auctioning C-band, for a familiar reason: fixed broadcast satellite services are squatting on the spectrum, said CK Foong, head of regulatory affairs for Axiata Group, a multinational, Malaysia-based mobile provider. But while US C-band satellite use has been declining, it's more widely used in Asia because it has less rain fade than higher frequency bands, and there's a lot of rain in southern Asia.
"We're looking for innovative ideas from 3GPP for coexisting with fixed satellite services," said Prakash Moorut, Nokia Bell Labs head of spectrum standardization.
While the US may have just auctioned the right spectrum, Xu implied there's another big worry: the $81 billion cost of the auction. He didn't mention the US in his presentation, but suggested that deferring payments, or offering payment plans, will help carriers speed up their 5G rollouts by balancing spectrum payments with network building costs.
Wi-Fi 6E: Not a Done Deal
I was startled by how the Asian panelists made a vigorous argument against what the US knows as Wi-Fi 6E. The US led the way to declare the 5.9-7.1GHz band an unlicensed band for Wi-Fi applications, but whether that band should be licensed or unlicensed is still under debate in many countries.
Foong went in hard on Wi-Fi. "Unlicensed spectrum cannot guarantee good quality," he said, talking about how the Wi-Fi at his house would "seize up" even though he has a mesh network with four units. "The mobile industry has been banking on licensed spectrum for the last 30 years."
Foong admitted that shared-spectrum schemes, such as Qualcomm's 5G NR-U, could "be a halfway" solution. NR-U does for 5G what LAA, Licensed Assisted Access, did for 4G. In the 4G realm, all three of our major carriers have put up panels outdoors in city centers that use 5GHz Wi-Fi spectrum as a supplement for their licensed spectrum; that's known as Band 46 in 4G parlance. Our tests have shown that 4G LAA gives 5G-like speeds.
Qualcomm oddly hasn't wanted to talk about NR-U recently, though, declining to discuss it when it launched its new X65 modem chipset. (I asked.) Hopefully we'll hear more about this technology over the next year.