A Low BER Cooperative-adaptive-equalizer for Serial Receiver in HPC Networks.

With the evolution of high-performance computer and data center interconnect communication rates from 53.125Gbps to 106.25Gbps, high-speed serial interfaces face a dramatic increase in BER challenges, which seriously affects interconnect performance and system stability. To address the challenge of high BER of 106.25Gbps PAM4 receiver, this paper proposes a cooperative adaptive equalizer structure, which adopts three equalizers and adaptive cooperative equalization algorithm to achieve low BER under large insertion loss conditions. In addition, a blind adaptive equalization algorithm based on judgment feedback equalizer is proposed to shorten the link training time. In this paper, a 12nm CMOS process is used to design a receiver based on cooperative adaptive equalizer. Simulation shows that the receiver with cooperative adaptive equalizer can support BER less than e-12 for a de-emphasized l06.25Gbps PAM4 signal after 34.3dB @ 26.5625G Hz channel, and the convergence period is less then 0.2 us.