Demonstration of Real-Time Burst-Mode Digital Coherent Reception With Wide Dynamic Range in DSP-Based PON Upstream

This paper proposes a real-time burst-mode coherent receiver (BMCR) that enables wide dynamic range reception for future passive optical network (PON) applications, wherein two key burst-mode components are implemented; an automatic gain controlled semiconductor optical amplifier (AGC-SOA) for optical power equalization and a real-time digital signal processor (DSP) with a frame detection (FD) function. The AGC-SOA greatly increases the receiver dynamic range by reducing the impact of quantization errors in the analogue-to-digital conversion used for DSP-based signal demodulation while the FD function detects burst frame arrivals for frame-by-frame optimization of tap weights of an adaptive filter in the DSP. Successful real-time reception of 20 Gb/s single polarization quadrature phase shift keying burst signals with wide dynamic range of 22.0 dB is experimentally demonstrated. New system configurations of the DSP-based coherent PONs using the BMCR and wavelength plans assigned to the new systems are also proposed to offer a smooth migration from existing PONs.