Analog Devices Inc. (ADI) and NEC are collaborating to provide 5G O-RAN massive MIMO radio for Rakuten Mobile. ADI’s fourth-generation software-defined radio is designed to support wireless applications such as massive MIMO and small cell systems, simplifying design and lowering power consumption. The radio unit has a 5G open vRAN (virtual RAN) interface corresponding to Rakuten Mobile’s virtualized end-to-end native cloud mobile network. The system performs digital pre-distortion in addition to digital beamforming.
In an interview with EE Times, Joe Barry, VP of Wireless at ADI, said, “Rollouts are progressing from coverage to capacity deployments with standalone 5G functionality, and we’re seeing the potential of virtualization of the networks. This effort is establishing the first leg of 5G — ultra-high-speed mobile data access to the mobile user. Achieving the full potential of 5G will come from reaching the emerging opportunities in Industrial, Transportation, Medical and immersive consumer markets. With such a diverse set of use cases across so many markets, robust and disruptive ecosystems are required to tackle these challenges.”
The challenges of 5G
Telecom providers are virtualizing their networks as the next evolution of communications. The combination of 5G and the cloud, via cloud radio access network (RAN) technology, promises to change the mobile business by cutting costs and opening up new services. According to analysts at HSBC Global Research, the potential benefits of this technology combination will help new players emerge around the globe.
RAN is a key element of mobile communications and plays a role in covering medium and large geographical areas in 5G networks. 5G RAN focuses on lower and mid-range radio frequencies, such as frequencies below 6 GHz, which can cover a wider area but carry less data.
Mobile networks are complex and require a very close link between hardware and software components. Cloud RANs promise to virtualize the network’s radio functions, separating the hardware from the software components and allowing operators to deploy ready-to-use equipment. The computing capacity and power are scalable as needed and can, therefore, be allocated when needed.
“In a traditional radio access network (RAN), the digital processing is done onsite,” Barry said. “With virtualization, much of the network function can be done in the cloud. Most early installs of 5G were non-standalone (NSA) and not virtualized; in the next wave, standalone (SA) installs will be the norm, and will evolve to virtualization (be it either vRAN or O-RAN flavor). This cloud-native architecture improves operational flexibility and supports advanced features including network slicing, enabling much of the potential of 5G. Network operators can now address unique use cases for private networks, Industry 4.0, massive IoT, transportation, construction and so on. We are only at the cusp of what is possible with a virtualized 5G network, but early indications are showing real promise,” said Barry.
Virtualization involves decoupling software from hardware, allowing network operators to automatically develop and deploy services that can be customized with virtual machines, thus lowering costs.
NEC and ADI
The goal of collaboration, as Barry pointed out, is to advance 5G connectivity. This ecosystem is so complex that the parties involved are looking for continuity solutions to cut downtime and cost, moving towards a virtualized network. ADI’s fourth-generation broadband RF transceiver integrates four-channel transmitters, receivers, and digital pre-distortion (DPD) in a single chip. The radio is completely software reconfigurable and covers all frequency bands below 6GHz, simplifying radio projects. NEC’s 5G equipment supports the digital beamforming.
“The new collaborations in 5G are leading to a vibrant marketplace. In the RU (radio units), we’re seeing innovation in 5G radios that solve the size, weight, power and cost challenges by combining ADI’s technology solutions with silicon and IP partners. As implementation expands across to the other applications, it is the robust ecosystem that will foster new innovation and solutions to realize the promise of 5G,” said Barry.
Considering that a 5G massive MIMO radio has up to 16 times more radio channels, and four times the bandwidth of traditional macro radio, Barry outlined how the technology innovation required to build these radio units (RU) is remarkable. He added, “the first hurdles are size, weight, power, and ultimately cost, which are significant to solve. Then layer on widening bandwidths, which push performance requirements, and frequencies above 3GHz, which increase the co-location interference risks. It is a multi-dependent variable challenge with many hidden problems. It is innovation at the circuit and architecture level that is successfully enabling M-MIMO for 5G. Over five generations, Analog Devices (ADI) has answered these SWaP challenges directly by increasing the channel count density integration, increasing the supported radio bandwidths by >10X, and reducing the power per channel down by >10X. ADI’s legacy, expertise and significant investment in developing its Software Defined Radio platform solved these challenges, enabling the vast majority of 5G M-MIMO radios in the world.”