Nokia's Bell Labs, Deutsche Telekom's T-Labs and the Technical University of Munich have achieved speeds of 1Tbps over fiber using a new modulation approach.
The experiment was conducted over a Deutsche Telekom optical fiber network as part of the Safe and Secure European Routing (SASER) project.
To achieve the speed, the partners developed a modulation approach known as probabilistic constellation shaping (PCS), which uses quadrature amplitude modulation to dynamically adapt transmission rates to channel conditions and traffic demands.
PCS modifies the probability with which constellation points are used to prefer points with lesser amplitude to transmit signals, which generally are more resilient to noise, Nokia said. This allows transmission rates to be tailored to fit transmission channels, delivering up to 30% greater reach.
"Future optical networks not only need to support orders of magnitude higher capacity, but also the ability to dynamically adapt to channel conditions and traffic demand,” Nokia CTO and Bell Labs president Marcus Weldon said.
“PCS offers great benefits to service providers and enterprises by enabling optical networks to operate closer to the Shannon Limit to support massive data center interconnectivity and provide the flexibility and performance required for modern networking in the digital era."
The Shannon Limit is the theoretical maximum capacity of a communications channel to transmit signals without error, based on the signal to noise ratio. Nokia said the trial on Deutsche Telekom's fiber network was close to the Shannon Limit of that channel.