Abstract

Kecent rapid progress in the video technology permits high-quality digital CATV systems. By using the video-compression standard MPEG2 the NTSC video signal will be coded as 6-Mbit/s digital data. Future video services, such as video-on-demand and interactive video service, will require a large number of digital video data over several hundred channels. To transport or distribute these large-capacity digital data, an optical transmission system is indispensable. Among the several optical transmission systems,^1,2 an intensity-modulation-direct-detection (IM-DD) system with time-domain multiplexing (TDM) is the most applicable candidate because of its high-speed data-transmission capability, freedom from carrier cross talk, and simple system configuration.³ With the assumption of a 10-Gbit/s data-transmission rate, over 1000 channels of MPEG2 data can be readily broadcasted. Futhermore, high-speed digital data, such as a digital HDTV video of over 100 Mbit/s, can be also mixed in a 10-Gbit/s data stream. In the IM-DD TDM system, however, there still remains the critical problem of selecting an appropriate channel from the high-speed TDM data sequence. We propose a novel, easy channel-selecting scheme for TDM digital-video distribution systems. A compact, automatically controlled smart optical terminal for demonstrating a large-capacity digital-video distribution system handling over 10 Gbit/s has been developed.

© 1994 Optical Society of America