Telecoms equipment maker ZTE Corporation (ZTE) said it completed data signalling at speeds of 400 Gigabits per second (Gbps) over a distance of more than 5,000km, setting a benchmark for the global optical networking industry.

The industry-first data transmission was achieved on a wavelength-division multiplexing (WDM) system with 100Ghz channel spacing. Data was transmitted through 25 reconfigurable optical add-drop multiplexer (ROADM) nodes without an electrical repeater, the firm said. 
ZTE said it used a unique frequency algorithm to overcome the issue of signal degradation, a common industry challenge in wideband communications over long distance. The success of this transmission laid the technical foundation for further development of global high-speed broadband networks.

With the growth of global broadband services, high bandwidth transmissions have become a basic requirement for communication networks. The long-distance transmission capability of a high-speed signal is a key component in the development speed of communications and services on a network. Because of this, 100G and 400G technologies are becoming key components of the world’s telecommunications industry infrastructure.

"ZTE has been dedicated to research of 100G and 400G/1T high-speed transmission solutions for many years,resulting in a variety of products and applications. In February 2011, ZTE became the world’s first company to transmit a single-channel 11.2Tbit/s optical signal. It also completed a 641km transmission at 1Tb/s in standard single-mode fibre, a new world record at the time. In July 2011, ZTE became the first in the industry to complete a 24Tb/s (24*1.3Tb/s) WDM signal transmission," the company said.

In February 2012, ZTE and Deutsche Telekom successfully completed a 2,450-km long-distance hybrid transmission of 100G/400G/1T signal in Germany. ZTE also used its patented technology to implement what was then a world-record 2,800-km long--haul 400G transmission without an electrical repeater in September 2012.