Byung Tak 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.

The SFP transceiver for 10Gbps asymmetric next generation-PON ONT

We present the first cost-effective 10 Gbps SFP transceiver module as ONT solution for both NG-GPON and NG-EPON compliant in asymmetric architecture.

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

Distributed IPTV system for personal broadcasting service

In this paper, we propose a distributed IPTV system by which each program provider (PP) possess a light-weight software-based IPTV head-end station, and subscribers watch an aggregated IPTV channel. In the proposed system, 1) each media belongs to the distributed PPs is automatically streamed at a scheduled instance; 2) each streamed media can be aggregated in real-time according to scheduling information, and delivered to subscribers in the form of a single IPTV channel.

FTTH-based IPTV testbed in Korea

The IPTV service is a worldwide trend, however it has been delayed in Korea. ETRI has been building own FTTH service center connected with commercial FTTH networks. We describe the architecture and related technologies.