Rakuten Mobile has joined forces with two of its many suppliers – RAN software vendor Altiostar and 5G radio provider NEC – to demonstrate interoperability in a multivendor O-RAN 5G network with Massive MIMO antenna arrays. Altiostar integrated the O-RAN distributed unit (O-DU) functionality of its vRAN with NEC’s O-RAN Radio Unit (O-RU) using control, user, synchronization and management plane protocols based on O-RAN Alliance guidelines. The 5G layer was built using container network functions (CNFs) running on the same cloud infrastructure that Rakuten has deployed to support its live 4G network. As part of the management-plane integration, Altiostar adopted a hierarchical model that allows the O-DU software to manage the NEC radio unit, including software updates, radio unit configuration,…