NTT DOCOMO, Fujitsu and NEC claim to have achieved the ‘world’s first carrier aggregation [CA] using 5G frequency bands in a multi-vendor Radio Access Network (RAN)’. In a joint press release, the companies said that interoperability with multi-vendor 5G base station equipment was achieved ‘in compliance with specifications established by the Open Radio Access Network (O-RAN) Alliance’. DOCOMO confirmed that CA used the 3.7GHz and 4.5GHz bands designated for 5G networks, and noted that by bundling LTE bands, downlink speeds of 4.2Gbps ‘will be achievable, enabling ultra-fast data transmission’.
The statement went on to point out: ‘DOCOMO already provides commercial 5G services in Japan through a multi-vendor RAN that connects baseband units and remote radio units manufactured by Fujitsu and NEC based on O-RAN’s open fronthaul specifications. The same system configuration was used to achieve this 5G carrier aggregation.’ Going forward, the three firms will continue working toward the early introduction of commercial 5G CA services, they said.
In a related development, DOCOMO and NEC also announced that they have successfully expanded multi-vendor interoperability by ‘interconnecting a new 5G base station baseband unit (5G-CU/DU), developed by NEC and Samsung Electronics and compliant with O-RAN Alliance specifications, with 5G base station remote radio units (5G-RUs) of other vendors on DOCOMO’s commercial network’. The move should make it easier to drive the rapid and flexible deployment of 5G services across Japan.