DSP implementation issues in 1000BASE-T Gigabit Ethernet

This is the second part of a tutorial on 1000BASE-T, physical layer of Gigabit Ethernet over copper. A general presentation of the 1000BASE-T standard was given in a previous communication [Azadet, 1999]. In this paper we focus on one of the main challenges in Gigabit Ethernet: DSP implementation. After presenting a reference implementation of the receiver we describe low-power digital adaptive filter architectures, and techniques for combining Viterbi and Decision Feedback Equalizers (DFE). The last section studies the critical path and complexity of the joint Viterbi/DFE decoder.