Mystery radio vendor in Telus open RAN is Canada's BMI

Telus executives would have regretted their choice of Huawei when the Canadian government, among others, ordered telcos to remove the controversial Chinese vendor from 4G and 5G networks. By May 2022, when the decision was announced, Telus had become heavily reliant on Huawei's 4G products across a nationwide network it shares with Bell, another big operator. Under government rules, those Huawei products must be gone by the end of 2027.

Anticipating a clampdown, Telus had introduced Ericsson, Nokia and Samsung as 5G vendors back in 2020 and was boasting population coverage of 80% just two years later. But the government decision also made it a firm advocate of open RAN radio access network (RAN) technology.

By allowing telcos to combine different vendors at the same mobile site, the design principle would also help Telus to avoid a Huawei-like situation in future, it believed. "We wanted to get to a position where we would never be locked in with any supplier again," said Bernard Bureau, the company's vice president of wireless strategy and 5G services, during a presentation at the FYUZ event in Dublin this week. Back in February, Bureau kicked off an open RAN deployment led by Samsung. By 2029, his goal is to have open RAN installed across the whole network.

What this means for Ericsson and Nokia is currently unclear because of today's focus on the Samsung-led rollout. Besides using the South Korean vendor's software, Telus is also buying its radio units across much of the footprint. But in a proper demonstration of a "multivendor" open RAN, it is elsewhere pairing Samsung's software with radios from a third party whose identity has remained a secret – until now.

The company is a relatively obscure manufacturer called Bluewaves Mobility Innovation (BMI), according to three separate sources. Based in Ontario, it is down to provide a chunk of the frequency division duplex (FDD) radios that Telus will deploy for open RAN. Other FDD units are to come from Samsung, which will also stump up radios for massive MIMO, an advanced 5G technology. Pairing vendors in massive MIMO is reckoned to be a major challenge.

Bureau, however, has previously downplayed concern about integration difficulties. In the case of massive MIMO, he told Light Reading earlier this year, the "single vendor" decision was taken because Samsung was the only radio supplier with a product spanning a required 450MHz midband spectrum range and able to support 200MHz within that. "It was difficult to find another supplier," he said.

Converting the unconverted

The project is still in its early phase. Bureau's target, he told FYUZ attendees, is to bring open RAN to 4% of macro sites this year, 18% in 2025, 33% in 2026 and 47% in 2027 before the whole network is covered by 2029. But this does not mean ripping out the traditional RAN equipment that Telus previously installed. "We started the replacement project a couple of years before open RAN and have half of the network that is new traditional RAN equipment," he said. Across this footprint of sites, his ambition is to use a converter that changes the all-important fronthaul link between baseband software and radios from CPRI, the old proprietary tool, to eCPRI, its more open successor.

The aim, moreover, is not just to open the network but also to virtualize it through the introduction of general-purpose equipment and common IT platforms. Besides relying on Samsung and BMI for RAN products, Telus is using HPE servers equipped with Intel's Sapphire Rapids EE chips. All that sits on a cloud infrastructure platform provided by Wind River.

For Samsung, this has meant developing software that will run on those Intel chips rather than on the more customized application-specific integrated circuits found in traditional networks. The objective, said Bureau, is to avoid reliance on "proprietary hardware." In theory, Samsung should be able to use the same virtual RAN software on a general-purpose processor made by another company.

Critics complain that Sapphire Rapids EE is more customized than a standard processor. To cope with a resource-hungry RAN task called forward error correction (FEC), it includes a hardware-dependent "accelerator." Samsung relies on Intel for both FEC hardware and software, it told Light Reading. For its virtual RAN software to be totally independent, it would have to avoid using Intel's FEC in Sapphire Rapids EE.

Nevertheless, Bureau objects to the use of "inline" cards, which shift multiple RAN functions from the general-purpose processor to a more customized chip. While Ericsson's virtual RAN strategy closely resembles that of Samsung, Bureau's stance would seem to have implications for Nokia, which relies on inline cards supporting chips made by Marvell Technology.

Bureau also dismisses concerns open virtual RAN cannot match traditional, purpose-built 5G on performance and feature parity. "I can attest, with a lot of empirical data to prove it, that the performance of our open RAN construct actually exceeds traditional RAN," said Bureau. Simplification of the radio portfolio has been a further bonus, with Telus reducing the number of different double- and triple-band radios in use from 21 to just 12. That's a "meaningful reduction," he said.

Still, work on swapping Huawei and introducing open RAN has not been free of challenges. Because it is shared with Bell (each telco takes responsibility for one half of the country), the network supports about 50% of Canadian traffic, said Bureau, and is equipped with nine 4G spectrum bands and three for the newer 5G standard. "These swaps are really painful for us and probably a bigger deal for us than for other CSPs [communications service providers] because of the complexity of our network given the number of radios we have and the number of antenna parts we have in the network," said Bureau.

Operators in other markets will be closely monitoring the rollout to see if performance holds up and costs remain under control, especially in areas where BMI's radios are paired with Samsung's baseband software. But the message from Bureau continues to be that open RAN is delivering results – and manageable. "Telus is big in Canada, but we are not big on the global stage," he said. "If we can handle it, there are lots of CSPs that can."