LAUSR

Abstract The use of a digital pre-distortion enabled C-band chirp-optimized electro-absorption modulated laser (EML) for Datacenter Interconnect Campus (DCI-Campus) is investigated for the first time. Pre-distortion techniques, specifically digital pre-equalization (Pre-EQ) and look-up-table (LUT), are applied to mitigate bandwidth limitation and nonlinear distortions, respectively. In an intensity modulation and direct-detection (IM/DD) system utilizing an EML, fiber dispersion induced frequency selective fading (FSF) is related to the chirp factor of the EML. To better suppress the FSF, the bias voltage of EML needs to be set to obtain a small positive or even a negative chirp factor, while the modulation nonlinearity appears. Nonlinear distortions introduced during FSF mitigation can be suppressed by the LUT scheme. With the digital pre-distortion enabled chirp-optimized EML in the IM/DD system, a 43 Gbaud PAM-8 signal is successfully transmitted over 5-km SMF-28, with a BER under the threshold for hard-decision feed-forward error correction (HD-FEC).