Mun Seob Lee

Simple ring-type passive optical network with two-fiber protection scheme and performance analysis

A simple passive optical network with ring-type distributed optical networking units (ONUs) is proposed. The ring protection is performed by a clockwise and a counterclockwise circulating fiber. The protection-and-restoration time is measured to be less than 5 s, and depends on the optical switching and the autodiscovery process time. In spite of additional devices for protection, the system reliability is enhanced so that the expected downtime decreases from 41.3 to 28.9 min/yr. The optimum condition to support the maximum number of ONUs is derived and verified by an optical link simulation.

Bidirectional amplification with linear optical amplifier in WDM-PON

To increase the system margin and service coverage in WDM-PON, bidirectional amplification with linear optical amplifier is demonstrated. We measured the sensitivity enhancement of 12.8 dB for downstream and 11.4 dB for upstream channel.

Self-amplified passive optical network using 8B10B line coding properties in Gigabit-Ethernet protocol

A cost-effective self-amplified network in a Gigabit-Ethernet passive optical network is demonstrated using 8B10B line coding properties. We explain the operational principles and experimental results including transmitter and receiver margin for an upstream channel.

Fabrication of 2.5 Gbps Burst-mode Receiver and its Full Compliance to GPON

In the current GPON market and standard, the line bit rate requirement is changing from 1.25 Gbps to 2.5 Gbps. We fabricate a 2.5 Gbps burst-mode receiver with commercially available blocks and optimize it with an APD bias control. A burst-mode measurement setup is made for the full compliance test with the GPON standard. The device meets the partially defined 2.5 Gbps specs in the current ITU G.984.2 standard, also, supports 1.25 Gbps specs for the coexistence issue in an access network. The full-compliant measurement values can be used as a guideline for fixing