Abstract: The high-speed signal transmission system of the new generation high-performance computer is realized by 56 Gbps PAM4 signal, and the transmission channel spans multiple PCB boards and multi-level connectors, so the design of signal integrity is facing great challenges. A simulation and verification scheme of 56 Gbps high-speed signal transmission system for the whole channel is proposed. Through plate parameter calibration, connector parameter test, and PCB wiring model extraction, a more practical complex transmission channel model is established, and the whole channel collaborative simulation experiment is carried out. Through the simulation experiment and iterative design, the stable and reliable transmission of 56 Gbps PAM4 high-speed signal is successfully guaranteed.

Key words: high-speed signal, PAM4, signal integrity, simulation