Japan's NTT DoCoMo and NEC have completed joint verification trials of Massive MIMO technology for future 5G base stations.
The trials in central Tokyo and the Kanagaawa Prefecture of Japan used NEC's massive-element active antenna system (AAS), achieving spectral efficiency eight times higher than LTE.
NEC's AAS supports the low super high frequency (Low-SHF) radio band. The SHF band encompasses centimeter-wave spectrum in the 3-GHz to 30-GHz band, and Low-SHF refers to spectrum in the 3-GHz to 6-GHz frequencies.
The vendor said its AAS adopts a fully-digitized antenna beam control technology to improve the precision of beam forming.
The technology is also capable of forming beams to counteract interfering signals, as well as beams that improve communication quality by combining the multi-path of its own signals with the direct waves.
"Thanks to NEC's contribution on the massive-element AAS supporting the low-SHF band, we were able to achieve highly successful outcomes from the trials," commented Takehiro Nakamura, managing director of NTT DoCoMo's 5G Laboratory.
"We expect NEC to continue pursuing high-speed, large-capacity communication using the low-SHF band and contributing to our commercialization of 5G."