Vodafone's Ker Anderson used to be lumbered with 5G radio units that each weighed about 60 kilograms, enough to buckle any poorly reinforced pole, and "burned electricity for fun." These massive MIMO boxes, incorporating 64 transmitters and receivers per unit (64T64R), are the high-performance engines of 5G, designed to last for years. But installing them has been slow and costly, Anderson admits.
The UK operator believes the move will ultimately pay off. Rivals have used smaller and more lightweight panels, featuring only eight transmitters and receivers per unit (8T8R), said Anderson, Vodafone UK's head of radio and performance, during a media roundtable this week. "I think they will regret it and have to go and upgrade again. We made the decision to go future-proof from the beginning."
The good news is that the massive MIMO units Vodafone buys from Ericsson, its main 5G supplier, have suddenly become a lot smaller and cheaper to run. After a product refresh by the Swedish vendor, Vodafone is switching to a new line-up of boxes that each include just 32 transmitters and receivers (32T32R). Those weigh half as much, making them easier to install, and perform just as well as the older boxes, says Anderson.
It ain't (as) heavy – rooftop-mounted massive MIMO units from Ericsson.
Importantly, they also consume far less energy – about 43% less each day, Vodafone says, after running trials. It now intends to buy 1,500 of the units from Ericsson and install them across 500 of its roughly 18,000 UK mobile sites by the end of next year. That deal is a validation of Ericsson's recent claims about the size and energy efficiency of its latest products.
Anderson has no plans to swap out any of the 64T64R units that have already been installed, which means some 5G sites will continue to gobble energy. "That is going backwards," he said, when asked if an overhaul would happen. "From a network performance and 5G rollout point of view, let's keep going. Otherwise, it is refitting and making no progress."
Much slower than 4G
Rollout still seems to be happening far more slowly than it did with 4G. EE (today a part of BT) managed to cover 90% of the UK population with its 4G network just two years after launching the service. Having launched 5G in mid-2019, the UK incumbent recently claimed coverage of just 40%. Vodafone is not disclosing the number but says its population coverage will be "a bit less" than BT's. As for the other operators, Three last month said its 5G network covered 30% of the "outdoor" population, while Virgin Media O2 – like Vodafone – is not disclosing a figure.
From Vodafone's perspective, the use of big and heavy boxes partly explains why deployment is taking longer. "Big, lumpy heavy objects require steel work and quite a lot of plant on site to install in a safe manner," he said. While the latest Ericsson kit should make a difference, the physical process of upgrading "is a lot more work than with 4G," said Anderson.
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Vodafone's 5G network will not be entirely free of 8T8R units, but its use of that technology will remain very limited, says a spokesperson. Meanwhile, the extent to which Vodafone's competitors rely on easier-to-install but less capable 5G equipment is not entirely clear.
At the time this article was written, neither O2 nor Three had been able to provide details of their massive MIMO strategies. BT has made some use of 8T8R 5G units, acknowledged a spokesperson for the operator. While that has usually been in rural areas with less demand for capacity, they have also been used to get around certain "practical constraints," such as the difficulty of obtaining permits for a massive MIMO installation.
The incumbent's broad strategy, however, has been to install 64T64R units in densely populated urban areas. And, like Vodafone, it is now shifting its focus to 32T32R "with the reduced power consumption it brings," says BT's spokesperson.
Open RAN risks
Arguably, the bigger risk for Vodafone is its reliance in some parts of the country on open RAN, an immature technology that no other UK operator has included in its 5G strategy so far. Apparently disappointed with Nokia's offerings, which are being phased out of its network in London and parts of the southeast, Vodafone's only real alternatives when the UK government decided to ban Huawei were to rely solely on Ericsson or to use new open RAN suppliers as well. It eventually chose the latter.
Accordingly, it is to replace about 2,500 Huawei sites with open RAN technology – provided mainly by South Korea's Samsung. While these sites mainly seem to be in less demanding rural areas, various European operators doubt open RAN will measure up on massive MIMO for several years. Anderson was not able to provide weight specifications for open RAN kit, pointing out that Vodafone announced its suppliers only as recently as June.
The other drawback is a lack of open RAN support for 3G, a technology that clearly irks Anderson but one that is still widely used by Vodafone customers. The operator has no desire to run a Huawei 3G network for several years in parallel with an open RAN network for 2G, 4G and 5G. Instead, it wants to phase out 3G as quickly as possible. But if it does not activate an open RAN site until 3G is retired, parts of the country could be without a Vodafone 5G service for years.