A 2-Lane Discrete Multitone Wireline Receiver Datapath With Far-End Crosstalk Cancellation on RFSoC Platform

Abstract

This brief presents a 2-lane discrete multitone (DMT) wireline receiver (RX) with a far-end crosstalk (FEXT) cancellation and its implementation on the ZCU111 RFSoC evaluation board for real-time functional verification. The RX datapath is implemented with the 64-parallel 128-tap multi-path delay-feedback (MDF) fast Fourier transform (FFT) to optimize resources and throughput. The multiple-input, multiple-output (MIMO) frequency-domain equalizer (FDE) compensates both channel insertion loss (IL) and FEXT based on coefficients computed from an on-chip pilot-assist channel estimation (CHEST). The platform includes a programmable logic (PL) for a DMT digital signal processor (DSP) running at 32 MHz, 2.048 GS/s data converters, and intersymbol interference (ISI)/FEXT board. This system enables the reflection of a realistic hardware impairment and real-time transceiver (TRX) operation with a quick bit error rate (BER) test. The measurement demonstrates that the MIMO DMT significantly improves a BER from 1.0E-2 to 5.8E-7 when the FEXT is canceled for a channel exhibiting 15 dB of IL and 10 dB of IL-to-crosstalk ratio (ICR) at Nyquist frequency.