Spreading Local 5G Powered by OSS--Tetsuya Iye, Ph.D.(Communication Engineering Dept. Kozo Keikaku Engineering Inc.)
ODAIBA IX Core/Industrial Transformation (IX) Leaders
Industrial Transformation (IX) Leaders (No. 10)

We spoke with Dr. Tetsuya Iye of Kozo Keikaku Engineering’s Communication Engineering Department—who says that “continuous development leveraging the scalability of open-source software (OSS) will accelerate the spread of local 5G”—about the development front line, the benefits of the OSS community, and current interest in the OAIBOX.

Kozo Keikaku Engineering (KKE) began as a structural-design consultancy for buildings and has since grown into a technology-oriented consulting firm. Guided by the philosophy of bridging academia, research institutes, and industry, KKE operates as an independent knowledge-engineering company. Having introduced computers to structural design as early as 1960—using simulation and seismic-design tools—the company soon expanded its activities into the information- and communications-technology field. A hallmark of KKE’s overseas partnerships is that they go beyond the simple developer–reseller model: the company promotes true engineering collaboration, working together with leading international firms to deliver superior products and services.

In the wireless domain, we have offered core services such as router prototyping with open-source software (OSS) and network-simulation analysis since the early 2000s. Starting in 2013, we began providing turnkey radio-prototype services that use overseas software-defined-radio (SDR) hardware. A Ministry of Internal Affairs and Communications (MIC) commissioned project on “5G enhancement” in FY 2019 marked our full-scale entry into 5G R&D, leading us to build a millimeter-wave SDR testbed. The software engine powering that testbed is the open-source platform OpenAirInterface (OAI).

Among the open-source projects related to 4G/5G, we were aware of platforms such as free5GC, SD-RAN, and SD-Core. However, even back in 2019, OAI clearly stood a step ahead: it is backed by a well-structured governing body, boasts a large and highly active community with frequent updates, covers a broad scope—from the Radio Access Network (RAN) and core network (CN) to user equipment (UE)—and can be attached to SDRs to run real, over-the-air (OTA) 5G links. Researchers, developers, and strategic members around the globe drive OAI forward around the clock, crossing time zones in lively discussions. From a user’s standpoint, any technical ambiguities can be resolved through community support; and once we contribute back, the distance between us and the community shrinks, giving us access to worldwide partners and enabling development that balances quality with speed. Since FY 2019 we have built up extensive know-how while “wrestling” with OAI. Late in FY 2022 we learned that Allbesmart LDA. of Portugal—founded by Paulo Marques and led by CEO Jorge Ribeiro, and the top corporate contributor to OAI—had released OAIBOX, a 5G base-station product built on OAI. We therefore concluded an exclusive distribution agreement and became the first company to bring OAIBOX to the Japanese market.

OAIBOX is an all-in-one package that delivers an experimental and research-grade open-source 5G base station. As soon as you purchase the unit you can power it up and have a working gNB—every component required to verify 5G operation is included. Despite being based on OSS, OAIBOX ships pre-tuned so that users obtain peak OAI performance and highly stable base-station behavior without the usual headaches of environment setup and parameter tweaking. Under the hood it is pure OAI, but Allbesmart has added a rich dashboard for visualization, stability-oriented parameter presets, and a textbook-style “Lab Manual”. Together these extras significantly lower the barrier to entering the 5G arena while complying with the complex 5G-NR specifications.

Interest has exceeded our expectations right from the launch—particularly the number of requests coming from the automotive sector has drawn attention within our company. When customers keep an active maintenance contract, they receive continuous software updates, and the intuitive “Dashboard” GUI automatically handles everything from pulling the latest source to build-and-deploy. Users are therefore freed from tedious manual steps. In practice, we envision a DevOps style environment in which the customer and our team jointly operate and evolve the system. Admittedly, the service is not inexpensive, but we are convinced that, over the long term, it will lead to a high-quality yet ultimately affordable and truly democratic solution.

OAIBOX comes with a comprehensive Lab Manual, so users can follow step-by-step instructions to deepen their technical understanding of 5G communications. For that reason, it is an ideal teaching tool for universities and training centers when educating students or junior engineers on next-generation wireless systems and their operating principles. In addition, it can serve as a fast track for obtaining an experimental base station license and conducting OTA trials.

Local 5G is still far from being as easy to operate as Wi-Fi, and proprietary commercial products often cannot be customized. We feel these factors create significant hurdles for product development and deployment. If, instead, we base systems on customizable software—such as open-source solutions—and make environment setup and operation as straightforward as possible, it should accelerate new use-case exploration and ultimately help expand the local 5G market.

As mobile networks evolve from 4G to 5G and on toward 6G, their technical specifications are becoming ever more sophisticated and complex. Consequently, the hardware and software needed to emulate 5G communications are harder to develop, and researchers and engineers must invest considerable time and effort just to build a workable platform for advanced wireless R&D. OAIBOX is, in our view, a practical tool for overcoming these challenges.

The XGMF / ODAIBA IX (Industrial Transformation) Core will host a workshop entitled “Developing Cheaper, More Democratic Ways to Harness Local 5G as Its Functions Stabilize and Costs Fall” on Thursday, 19 June 2025, at the Sekisui Chemical Minase Innovation Center in Osaka. A live-streamed online broadcast will be open to everyone. For details, please visit here.

(TeleGraphic Editorial Board)