Design Considerations and Performance Trade-Offs for 56Gb/s Discrete Multi-Tone Electrical Link

For communicating over mid-to-long-reach electrical links at a data-rate above 56Gb/s, ADC-based receiver (RX) has become a dominant architecture due to its strong equalization capability using complex digital signal processing algorithm benefiting from the extreme process node shrinkage. This paper discusses the design of >56Gb/s DAC/ADC-based wireline transceiver (TRX) with discrete multi-tone (DMT) modulation. Some notable differences between wireless orthogonal frequency division multiplexing (OFDM) systems and wireline DMT systems are discussed, and some practical design considerations for a multiple tens-of-Gb/s DMT RX is provided.