13 Sep 2013
Japanese telecoms giant Softbank and China-based vendor Huawei have completed the deployment of what they claim is ‘the world’s first trial LTE-Advanced (LTE-A) network in the 3.5GHz spectrum band’. According to a joint press release, a pre-commercial performance evaluation conducted in a recent demonstration held in Tokyo’s district of Ginza showed that the network could provide a solution for co-frequency band interference; in addition, the maximum download speed achieved over the network was reported as 770Mbps, while an average downlink of 500Mbps was achieved over multiple sites using Carrier Aggregation (CA), Coordinated Multi Point (CoMP) and Cloud BB (Baseband) technologies. Softbank also demonstrated a ‘five-carrier CA’ technology for Time Division Duplex (TDD)-LTE in the 3.5GHz frequency band using a prototype system that can provide maximum download speeds of 1.2Gbps when run on Huawei’s Ultra-wideband Remote Radio Unit (RRU). If deployed, a combination of Ultra-wideband RRUs can support more than 100MHz of instantaneous bandwidth and can be customised on-demand to accommodate new spectrum. Further spectrum in the 3.4GHz-3.6GHz band is expected to be allocated for introduction of commercial 4G networks in Japan by 2015.