DBSCAN-based decision technique for 60Gbps PAM-8 IM/DD system

The intensity modulation and direct detection (IM/DD) systems have been widely investigated and demonstrated to fulfil the requirement of short reach data communication links with simple implementation. DMLs are a low cost solution for IM/DD systems due to their low power dissipation, small footprint and high output optical power. However, for DMLs, the driving current can influence the optical density at its active region, hence the intrinsic chirp affects the generated optical carrier and results in distortions of the signals, which reduces transmission rates and signals decision accuracy. We propose a machine learning-based decision technique to mitigate nonlinear distortions of the DMLs without using any nonlinear processing, and demonstrate a 60-Gb/s PAM-8 IM/DD system using a DML. About 0.6-dB receiver sensitivity improvement is achieved after 2km transmission.