Burst Mode DSP and Preamble Design for Low Complexity TDMA CPON Upstream Transmission

We experimentally and numerically demonstrate a 100 Gbit/s burst-mode coherent upstream transmission for Passive Optical Networks (PON), achieving a link budget of 38 dB without optical amplification. The system utilizes a novel 17.1 ns dual-polarization quadrature phase shift keying (DP-QPSK) preamble to enable reliable burst-mode digital signal processing (DSP) convergence. We pose particular emphasis on the robustness of the burst-mode DSP in correcting the frequency offset within the preamble duration. Considering different pulse shapes reveals that rectangular (RECT) pulses outperform root-raised cosine (RRC) shaping in terms of link budget and enable the use of low-complexity transmitter architectures, including 1-bit digital-to-analog converters (DACs). Receiver bandwidth requirements are also investigated, showing that reduced bandwidth can be employed without compromising system performance. Long-term stability of the proposed system is validated through continuous operation over 12 hours and more than 300 burst transmissions, confirming the practical viability of the proposed system for next-generation coherent PON transmission systems.