• The data-hungry user base of Japan’s newest mobile operator continues to grow
• One of Rakuten Mobile’s current areas of focus is greater energy efficiency
• It is putting its RAN intelligent controller (RIC) to work next year as part of a broader campaign to reduce power consumption by up to 20% 

As Japan’s newest telco, Rakuten Mobile, continues to grow its customer base and network data traffic, it is introducing multiple green network initiatives, including the commercial deployment of its RAN intelligent controller (RIC) platform, that it hopes will lead to energy savings of between 15% and 20%. 

During a webcast briefing with analysts and the media on Tuesday (19 November), Sharad Sriwastawa, co-CEO of Rakuten Mobile and president of its vendor unit Rakuten Symphony, provided an update on the operator’s progress (of which more later). He outlined a number of initiatives, including one aimed at improving the energy efficiency of its network operations, something that all mobile operators are seeking to achieve in order to keep operating costs under control as more and more data is transported over their networks: Rakuten Mobile users, for example, are currently consuming 30 GBytes of data per month. 

Sriwastawa noted that the “focus for this quarter and the coming year” is to achieve “anything between 15% to 20% saving on overall power consumption” by mobile base stations and its portfolio of datacentre facilities: Rakuten Mobile currently has four central datacentres, 43 regional datacentres, and 1,906 edge datacentres (with more than 38,000 servers in operation) and over 64,000 macro cell sites. 

“On RAN [radio access network] solutions, we are utilising various techniques – shutting down the MIMO [multiple input, multiple output radios] and shutting down the servers” as well as enabling power-saving states for servers that reduce power consumption at low-use times, noted Sriwastawa. There are also “hibernation” states that can be implemented for data transport network systems. All of these energy-saving techniques are set to be implemented from the first quarter of 2025 and “we want to do all of these changes via RIC and NIC [network intelligent controller]”, running various AI-enabled applications that can automate the processes.  

It’s worth remembering that Rakuten Mobile’s network was designed and built from the beginning with automation in mind and even though it now has an extensive national network, it still has only about 250 network operations staff in total.  

Sriwastawa noted that there are obvious gains to be made in the RAN when some sites are not being used at all at certain times – for example, at train stations that are closed overnight or in office areas out of working hours. These networks are designed to have overlapping cells so there is, at least, some coverage if needed, “but the main gains come from the datacentres where the operator can implement multiple energy-saving applications developed by Intel.

Rahul Atri, president of Rakuten Symphony’s OSS business unit, added that the operator has been collecting and analysing customer, as well as network, data so that it can understand user and network traffic patterns. It is using the learnings from that data to develop RIC and NIC applications that can be used for automated network management processes.  

In addition to those internally developed apps, Rakuten Mobile will also use third-party RIC and NIC applications to address multiple requirements. “SON [self-optimised/self-organised network] applications are being developed into RIC apps,” while the company is also working with developers of energy efficiency, radio frequency (RF) optimisation and spectral-efficiency specialists. Atri referenced AirHop as an application partner, and is known to be evaluating applications from the likes of Cohere Technologies, which has developed a spectrum multiplier application, zTouch Networks and Rimedo Labs, which has developed energy-efficiency and traffic steering applications. 

You can find out more about the potential of RIC platforms and their associated applications, and more about AirHop and its engagement with multiple network operators, in TelecomTV’s recent free-to-download DSP Leaders Report, Open RAN: Advances in the RAN Intelligent Controller. 

Progress report

While Rakuten Mobile doubles down on its energy-efficiency efforts in the coming year, it will also be aiming to make more money, as well as save it. But to do that it’s going to need to attract a lot more customers. 

Rakuten Mobile, which started building its mobile network in late 2019, currently has just over 8.1 million customers, which gives it a 3.8% market share in a sector dominated by NTT Docomo, KDDI and SoftBank. Its customer base is growing steadily but slowly.

Rakuten Mobile generated third-quarter revenues of 72.5bn yen ($475m), up by 30.3% year on year, but it has a long way to go before it’s making money: Its operating loss for the third quarter was 50.6bn yen ($332m) – though that was at least about 30% better year on year – while its earnings before interest, taxes, depreciation and amortisation (EBITDA) loss shrunk by 70% to 10bn yen ($65m). Rakuten Mobile expects to reach EBITDA breakeven in December this year. 

The company’s parent, Rakuten Group, has always stated that Rakuten Mobile is an important part of the larger portfolio and that its value will come not just from its own operations but also from the traction it will bring to the group’s other services and applications (fintech, e-commerce and more), and that does appear to be working. According to Rakuten, Rakuten Mobile subscribers are spending almost 50% more via the group’s e-commerce platform, Rakuten Ichiba, than non-subscribers. For further details, see the company’s third-quarter earnings report. 

- Ray Le Maistre, Editorial Director, TelecomTV