China’s fibre diet was bulked out yet further this week with the news that China Unicom has tapped Nokia Siemens Networks (NSN) to deploy a 40Gbps-capable optical network for the operator.

The network will be 5,000km is length and will be able to handle 40Gbps per channel, based on dense wavelength division multiplexing (DWDM) technology. The seven provinces of Chongqing, Hubei, Anhui, Jiangsu, Fujian, Guangdong and Guangxi will have access to the network and the company said that the roll out paves the way for future upgrades to 100Gbps speeds, while also lowering costs by reducing the number of sites deployed.

“As one of the largest network operators globally, China Unicom understands the importance of investing in the latest technology,” said Markus Borchert, head of Greater China region at Nokia Siemens Networks in a statement. “Our 40G DWDM system will ensure a longer life cycle for China Unicom’s network by increasing its network capacity to handle data traffic growth. In fact, since CP-QPSK technology is being used for the first time in China, it will act as a new benchmark for enhancing transport performance and end-user experience.”

The equipment used in the NSN roll out includes its hiT 7300 DWDM system, with 40G transponder technology. This is based on the CP-QPSK modulation format, and avoids the needs for using dispersion compensating modules (DCM). The vendor said that this means lower latency connections and simplified amplifier design, which reduces overall deployment costs, reduces operating expenditure and speeds up service delivery. It also enables the use of pre-installed network infrastructure, which, NSN said, will help protect operators’ capital investments.

NSN has recently been trying to find a partner to buy a stake in the company, which has been said to have lost around $1bn in the last year.