A 56 Gbaud reconfigurable FPGA feed-forward equalizer for optical datacenter networks with flexible baudrate- and modulation-format

The staggering growth of datacenter traffic has spurred the rapid uptake of advanced modulation-formats to increase throughput. Commodity optoelectronic components are used for cost-efficiency, assisted with digital equalizers to mitigate their bandwidth limitations. With optically-switched datacenter architectures gaining momentum, reconfigurable equalizers are sought allowing the receiver to adapt to different fiber lengths, bitrates and modulation-formats associated to different optical paths. An FPGA-based feed-forward equalizer (FFE) reconfigurable in baudrate and modulation-format is demonstrated. We verify its performance with NRZ and PAM-4 experimental data up to 56 GBaud, investigate its accuracy and extract the optimum FFE implementation for different transmission scenarios.

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