Rakuten Symphony is set to hit an important open radio access network (RAN) feature target, but still has work to do in bolstering the technology’s ability to support brownfield network deployments.

Tareq Amin, group EVP for Rakuten, said during the company’s most recent first-quarter earnings call that its open RAN system was near software feature parity with already deployed network systems. This is important for operators as they look to further migrate their current networks toward an open RAN architecture.

Amin said this is a “very big inflection point for us where we will be at feature parity with all legacy software features that exist in brownfield operators. This is really very exciting, and this is what we’ve been focused on over the last year to enable brownfield deployment in commercial environments.”

The executive highlighted Rakuten’s extensive operating support system (OSS) advances, which include deployments across 11 customers and more than 100,000 platform users tapping into its more than 17 products. That depth generated $76 million in sales for Q1, which was nearly 15% more than it reported the previous year.

Rakuten established its Symphony division in late 2021 with a focus on expanding its open RAN architecture into more networks around the world.

The division initially housed the Rakuten Communications Platform (RCP) and Rakuten’s various open RAN technology assets and services. The RCP platform has since been rebranded as Symworld following its acquisition of Robin.io.

Amin added that Rakuten Symphony exited Q1 with more than $3 billion in its sales pipeline, which was down from the $4 billion he touted the previous quarter.

Despite that platform progress, Amin did admit to a pair of challenges that continue to impact open RAN adoption.

The first was a lack of hardware to support diverse spectrum bands used by legacy operators. This is a common issue for carriers that have operated for decades and have accumulated multiple spectrum bands to support services.

“Most mobile operators would require a need to consolidate electronics at their sites, so they would need not only single remote radio heads, but they might need dual-band, tri-band, high-power to meet a variety of spectrum bands,” Amin said. “To find this ecosystem wasn't easy, it was not trivial.”

The second issue is the software component of that first issue, which is the need to support carrier aggregation efforts in an open RAN deployment. Carrier aggregation is the combining of different spectrum bands to act as a single transmission channel that can support higher speeds and greater capacity.

“To go over not just only two-carrier aggregation but to support three-, four-carrier aggregation of both downlink and also uplink … that took a substantial amount of energy, but we're almost done; completed through the support of [carrier aggregation] features,” Amin said.

U.S.-based carriers AT&T and T-Mobile US both recently touted carrier aggregation milestones tied to their 5G network deployments. Those efforts were done with established legacy network partners like Nokia, Qualcomm and MediaTek.

Challenges aside, operators are continuing to slowly roll out open RAN architectures across their legacy operations.

Vodafone earlier this month said it turned on its first open RAN sites to support its 5G network. The 14 sites are now active in the towns of Torquay and Exmouth in the United Kingdom, covering approximately 87,000 people.

Vodafone has been a long-time backer of open RAN, striking collaboration deals with other operators and vendors to boost the ecosystem.

Research firm Analysys Mason noted in a recent report that Rakuten’s Amin stated during the MWC Barcelona 2023 event that he was “‘really, really disappointed’ with the limited adoption of open RAN by brownfield operators.”

“Some operators, notably Deutsche Telekom, NTT DoCoMo and Vodafone, have started to deploy open RAN in a few small areas, but according to a survey of 75 operators, conducted by Analysys Mason in Q4 2022, over 80% do not expect to implement multivendor open RAN in the urban macro network until 2026 or later,” Analysys Mason Research Director Caroline Gabriel wrote in the report.

“That leaves a hiatus during which operators cannot achieve the supply chain disruption and cost savings that they were targeting from open RAN, and challenger vendors cannot generate significant revenue.”