Burst-mode digital signal processing for passive optical networks based on discrete multi-tone

Driven by the ever-increasing capacity demands, digital signal processing (DSP) has been first applied to improve the performance of a 50G passive optical network (PON). The main challenge is implementing the burst-mode DSP to deal with the upstream burst signal. This paper proposes a burst-mode DSP using preambles designed for the 50G PON based on entropy-loading discrete multi-tone (DMT). The burst-mode DSP mainly includes the burst-mode timing recovery with the initial timing offset and the burst-mode frequency-domain equalizer with the initial tap coefficients. The experimental results of the 50G DMT PON demonstrate that the burst-mode DSP can achieve fast convergence based on the ∼27ns preamble with 800 samples. The proposed burst-mode DSP makes the DMT PON highly feasible to support non-residential point-to-multi-point applications such as passive optical local area networks.