pam 4d4D-PAM5 (Four-Dimensional Five-Level Pulse Amplitude Modulation) is a multilevel snaling scheme. In this encoding method, data is transmitted simultaneously over four wires, utilizing4D-PAM5 is the method used to transmit data at 1 Gbsec over four wire pairs using five snaling levels. It combines 8B1Q4, Trellis, Viterbi, and 4D coding and decoding, and is