Infinera, the provider of Intelligent Transport Networks, achieved two industry-first milestones for advanced coherent technologies that increase the capacity and reach of optical transport networks to the next level.
The first milestone drives optical transmission technologies to 100 gigabaud (GBaud), and the second milestone enhances modulation technology to 1024QAM (quadrature amplitude modulation).
These new technologies are designed to deliver the highest possible capacity on a single wavelength for varied distances, helping operators extract the best performance from their optical transport networks.
Optical transport networks are a critical component of the global communications infrastructure, enabling cloud-based services to reach users around the world, and rely on three axes for increasing transmission performance:
• Baud rate: The rate at which modulation symbols are sent. The typical deployed baud rate is 32 GBaud with the quadrature phase shift keying modulation carrying 4 bits per baud, resulting in 100 gigabits per second of transmission.
While industry opto-electronics are moving to 66 GBaud development demonstrations, Infinera is the first to showcase 100 GBaud using 32QAM to achieve a single-wavelength 1 terabit per second (Tb/s) data rate using multi-channel indium phosphide-based photonic integrated circuits (PICs) integrated with electronic driver and amplifier application-specific integrated circuits. This result was presented at the 2017 European Conference on Optical Communications (ECOC).
• Modulation scheme: Converts the bits to symbols. At ECOC, Infinera showcased the higher-order modulation scheme of 1024QAM using advanced constellation shaping algorithms and Nyquist subcarriers, allowing wavelengths to be spaced close to each other to maximize the data rate for a certain reach. The Infinera test bed used 66 GBaud at 1024QAM to reach 1.32 Tb/s, yielding spectral efficiency of 9.35 bits per second per hertz over 400 kilometers (km), an industry first.
• Channel count: Implements multiple parallel wavelengths on a single module to create a coherent super-channel. As baud rates increase, placing optical components closer together on an integrated chip reduces component size and power while increasing reliability.
Baud rate and modulation scheme have been addressed by the industry for some time, with Infinera now setting new milestones for each. Infinera’s PIC technology uniquely enables high-channel-count coherent super-channels. These innovative technologies indicate the next level of capacity and reach achievable in the years to come.
“Infinera is delivering optical engines at a faster cadence to help operators achieve exceptional capacity and reach performance on their transport network infrastructures,” said Dr. Dave Welch, Infinera Co-Founder and President. “As 5G wireless and cable video services take off, Infinera offers significant value to transport network operators by designing industry-first solutions.”