Hybrid DWDM-TDM long-reach PON for next-generation optical access

TLDR

The authors propose a hybrid DWDM‑TDM passive optical network architecture as a candidate for next‑generation optical access. The design merges access and backhaul in a single fiber, uses centralized carrier distribution with wavelength‑independent remote modulation, and employs a customer transmitter built from an electro‑absorption modulator integrated with two semiconductor optical amplifiers to achieve high gain, bandwidth, and support for large splitting and 10 Gb/s upstream. Experiments demonstrate a 100 km reach and 10 Gb/s upstream, enabling 17 TDM PONs at distinct wavelengths each serving up to 256 customers, for a total of 4,352 customers.

Abstract

A novel long-reach passive optical network (PON) architecture based on hybrid dense wavelength-division multiplexing (DWDM) and time-division multiplexing (TDM) is presented as a possible candidate for the next generation of optical access networks. The approach combines access and backhaul functions in a single optical network infrastructure that links end customers directly to core networks without the need for intermediate electronic conversions. A centralized optical carrier distribution and wavelength-independent remote modulation scheme is employed to avoid the potential inventory and deployment costs associated with the use of wavelength-specific lasers in the customer transmitter (TX). The customer TX is based on an electroabsorption modulator (EAM) monolithically integrated with two semiconductor optical amplifiers (SOAs), providing sufficient net gain and bandwidth to support large splitting factors and upstream bit rates up to 10 Gb/s. The experimental results reported show that the network, with a total reach of 100 km and an upstream bit rate of 10 Gb/s, can potentially support 17 TDM PONs operating at different wavelengths each with up to 256 customers, giving an aggregate number of 4352 customers in total.