Multi-level pre-equalization using binary analog FIR filters based on 28-nm FD-SOI for 20-Gb/s 4-PAM multi-mode fiber transmission

Abstract

We propose a novel multi-level pre-equalizer composed of multiple binary analog finite impulse response (FIR) filters. The performance was investigated using numerical simulation of a 20-Gb/s four-level pulse-amplitude-modulation (4-PAM) multi-mode fiber (MMF) transmission system. The analog FIR filters were designed using 28 nm fully depleted silicon on insulator (FD-SOI) based complementary metal-oxide-semiconductor (CMOS) circuits. The simulated CMOS circuits successfully compensated the multi-level signals distorted by modal dispersion. The error vector magnitude (EVM) of the transmitted 4-PAM signals was improved from 40% to 9%. The proposed design scheme will enable cost-effective, low-power analog FIR filters for multi-level pre-equalization.