Altiostar announced testing of massive MIMO 5G with vRAN in collaboration with NEC and Rakuten Mobile. The tests aim to ensure interoperability of multi-vendor systems based on the open specifications from the O-RAN alliance.
Altiostar is integrating the O-RAN Distributed Unit (O-DU) functionality of its virtual radio access network (vRAN) software with NEC’s O-RAN Radio Unit (O-RU) using fully compliant control, user, synchronization and management (C/U/S/M) plane protocols based on O-RAN Alliance guidelines. The 5G layer is built using container network functions that leverage Rakuten Mobile’s cloud infrastructure platform as part of its 4G network build out.
As part of management-plane integration, Altiostar is following a hierarchical model that allows the O-DU software to manage the NEC O-RU, including providing software upgrades, RU configuration, fault management and performance monitoring. This interoperability is being performed for 5G new radio sub-6 GHz massive MIMO O-RU and meets all the 3GPP downlink/uplink requirements, the company said.
Altiostar has pioneered RAN disaggregation since 2013 when it first introduced a split between the higher non-real-time layers of the protocol stack and the lower layers of the stack. The industry then standardized this concept in the 3GPP and what is now known as the option-2 split between the centralized unit and the distributed unit. This paved the way for operators to think differently when it comes to disaggregation and network deployment, according to Altiostar.
Further disaggregation was introduced by Altiostar in the form of a radio interface unit. The RIU incorporates lower L1 functionality and provides a gateway function that converts Common Public Radio Interface to/from Ethernet. By eliminating the high bandwidth and proprietary CPRI interface to the radio, Altiostar took a key step towards integrating legacy Remote Radio Head over an Ethernet transport network to O-DU functionality.
Using this technology, the first multi-vendor RAN was deployed at a commercial scale and paved the way for operators to engage radio vendors to build O-RAN compliant radios. Rakuten Mobile’s adoption of the platform has helped move forward the ecosystem and open interfaces in the industry.