Rakuten Mobile Deploys 1Finity Open RAN 5G Radios Across Japan Network

Rakuten Mobile announced that it has begun rolling out 1Finity’s Open RAN 5G radios throughout its nationwide network, extending the carrier’s 5G footprint and deepening its commitment to open, multi‑vendor architecture. The deployment, reported by several industry outlets, signals a strategic push by Japan’s newest mobile operator to diversify its supply chain and accelerate coverage in a market where spectrum is tightly contested.

Core developments

According to the company’s technical brief, the rollout utilizes 1Finity’s Open RAN kit, which bundles radios, baseband units and software that conform to O‑RAN specifications. The equipment is being installed at existing cell sites as well as new locations that were added during Rakuten Mobile’s 5G expansion plan earlier this year. The operator describes the radios as “software‑defined” and capable of supporting both sub‑6 GHz and millimetre‑wave bands, allowing the network to scale as demand grows.

Sources from The Fast Mode and SDxCentral confirm that the deployment is part of a broader effort to replace legacy, vendor‑locked hardware with open‑source alternatives. 1Finity’s solution is said to integrate with Rakuten’s cloud‑native core, which the carrier built in‑house after launching its commercial 5G service in 2020. By using an Open RAN approach, Rakuten can theoretically mix and match components from different suppliers, reducing dependence on a single vendor and potentially lowering capital expenditures.

Telecom Reseller and Mobile World Live report that the initial phase covers a “significant number” of sites in the Kanto, Kansai and Chubu regions, though exact counts were not disclosed. The rollout is being overseen by a joint team of Rakuten engineers and 1Finity specialists, who are conducting field trials to verify performance metrics such as latency, throughput and radio‑frequency efficiency.

Data Center Dynamics adds that the deployment also includes upgrades to back‑haul connectivity, leveraging Rakuten’s existing fiber infrastructure to ensure that the new radios can handle the higher data rates expected from 5G applications. The operator plans to continue expanding the Open RAN footprint throughout 2026, aligning with Japan’s national 5G target of covering 95 percent of the population by 2027.

Why it matters

Open RAN has been touted as a way to break the entrenched monopoly of traditional telecom equipment makers. By adopting 1Finity’s kit, Rakuten Mobile joins a growing list of carriers worldwide—including operators in Europe, the United States and Southeast Asia—that are experimenting with open, interoperable hardware. The move is especially salient in Japan, where the market has historically been dominated by a few domestic giants.

For Rakuten, the decision dovetails with its broader strategy of leveraging cloud‑native technology to differentiate itself from incumbents such as NTT Docomo and KDDI. The carrier’s 5G service is built on a fully virtualised core, and the Open RAN radios provide a matching “edge‑to‑core” architecture that can be updated via software rather than costly hardware swaps.

Analysts note that the Open RAN approach could accelerate the rollout of advanced use cases—such as private‑network deployments for manufacturing, low‑latency gaming and autonomous‑vehicle testing—by allowing faster integration of niche features that traditional vendors may not prioritize. Moreover, the modular nature of Open RAN can enable regional operators to source components locally, fostering a domestic ecosystem that aligns with Japan’s industrial policy goals.

From a cost perspective, open solutions are expected to drive down both upfront CapEx and ongoing OpEx. While exact savings figures have not been disclosed, the industry consensus is that software‑centric designs reduce the need for proprietary firmware updates and can be managed with fewer specialised staff.

Differing viewpoints and reactions

Industry observers are broadly supportive of Rakuten’s Open RAN push. A spokesperson for 1Finity, quoted in the Mobile World Live release, described the partnership as “a milestone for open, interoperable 5G in Japan,” emphasizing the company’s confidence in the scalability of its hardware.

Conversely, some analysts caution that the technology is still maturing. The Fast Mode article highlighted that while Open RAN promises flexibility, performance parity with established vendors remains a key benchmark. “Operators must ensure that the radio‑level quality of service meets the high expectations of enterprise customers,” the piece noted, without attributing the comment to a specific individual.

Telecompaper pointed out that the rollout could encounter logistical challenges, such as coordinating firmware updates across a heterogeneous equipment base and ensuring seamless handover between Open RAN and legacy sites. The article suggested that Rakuten’s in‑house expertise in cloud networking may mitigate these risks, but acknowledged that the full impact will only be clear after the network has been live for several months.

Despite these reservations, the consensus among the cited sources is that Rakuten’s deployment represents a tangible step toward a more open telecom landscape in Japan, and that the carrier’s willingness to experiment could encourage other operators to follow suit.

What’s next

Rakuten Mobile has outlined a phased expansion plan that will see additional 1Finity radios installed throughout 2026, targeting rural prefectures where coverage gaps remain. The operator also intends to integrate the Open RAN infrastructure with upcoming 5G‑Advanced features, such as enhanced mobile broadband (eMBB) and ultra‑reliable low‑latency communications (URLLC), once the relevant standards are ratified.

In parallel, 1Finity is expected to release firmware updates that enable advanced AI‑driven radio optimisation, a capability that could further reduce operational costs and improve spectrum efficiency. Both companies have signaled that they will publish performance data in a series of white papers later this year, offering the industry a clearer picture of Open RAN’s real‑world viability.

Regulators in Japan are monitoring the rollout closely. The Ministry of Internal Affairs and Communications has expressed interest in promoting open standards to foster competition, and may consider incentives for carriers that adopt Open RAN solutions. If Rakuten’s deployment meets its performance targets, it could become a reference model for future network upgrades across the country.

Ultimately, the success of the 1Finity‑Rakuten partnership will hinge on whether the open radios can deliver the same reliability and speed that consumers have come to expect from Japan’s high‑density urban networks. The coming months will test that promise, and the outcomes could reshape how Japanese operators build their next‑generation infrastructure.