Arria® 10 Transceiver PHY User Guide

ID 683617
Date 4/01/2024
Document Table of Contents Decision Feedback Equalization (DFE)

DFE amplifies the high frequency components of a signal without amplifying the noise content. It compensates for inter-symbol interference (ISI). DFE minimizes post-cursor ISI by adding or subtracting weighted versions of the previously received bits from the current bit. DFE works in synchronization with the TX pre-emphasis and downstream RX CTLE. This enables the RX CDR to receive the correct data that was transmitted through a lossy and noisy backplane.

The DFE advantage over CTLE is improved Signal to Noise Ratio (SNR). DFE amplifies the power of the high frequency components without amplifying the noise power.

Figure 231. Signal ISI