Acacia demos coherent module for DCI, Metro and Long-Haul

At OFC 2018 in San Diego, Acacia Communications demonstrated its AC1200 Coherent Module, which supports transmission speeds of up to 1.2 Tbps in a footprint that is 40% less than the size of the 5” x 7” modules supporting transmission speeds of 400 Gbps today.

The module is based on Acacia’s Pico digital signal processor (DSP) ASIC, which is operating at 600 Gbps transmission speed, using 64QAM modulation for the demonstration, and utilizes two wavelengths that can be configured to support from 100 Gbps to 600 Gbps capacity each. Advanced three-dimensional (3D) shaping features may be optimized to enable performance approaching theoretical limits on a wide range of network configurations.

Acacia said its 3D shaping allows fine-tuned adjustment of the modulation characteristics to provide network operators with the flexibility to customize the AC1200 transmission to their network requirements. The key features enabling 3D-shaping include:

• Shaping of the constellation points’ probability to optimize capacity using Acacia’s patented Fractional QAM modulation;
• Shaping of the constellation points’ location to optimize reach; and
• Shaping of the spectral width to match the available channel passband by adapting the baud rate.

Sampling is underway and commercial production is slated to begin in the second half of 2018.