Simultaneous Transmission and Amplification of 622 Mb/s, 10 FM NTSC Video Channels and 3 FM HDTV Components Using a High Gain Erbium Doped Fiber Amplifier

Abstract

The evolution of the SONET as a transport for future switched digital Broadband-ISDN services coupled with the advances in using subcarrier multiplexing (SCM) as an economical alternative to distribute NTSC and future HDTV video channels, has fueled research in systems capable of transporting both services. The simultaneous transmission of baseband digital signals and SCM, FM video channels on one wavelength has been proposed as a bandwidth efficient and cost effective way to distribute high speed digital signals and a large menu of video channels to subscribers [1], [2], [3], but previous experiments required high bandwidth optoelectronics and had limited power budgets. Erbium doped fiber amplifiers (EDFAs) with their high gain, insensitivity to modulation formats and ease of integration with lightwave systems offer an elegant way to overcome splitting losses in distribution systems. We report an experiment where a single laser was modulated with a signal with RF bandwith of 2 GHz containing 622 Mb/s (SONET STS-12 rate) at baseband, 10 SCM FM NTSC video channels and 3 SCM FM HDTV components. The signals were further transmitted over 15 km of fiber and distributed to 8192 terminals. A system power budget of 49.5 dB was made possible by an in-line EDFA pumped at 532 nm with a gain of 31.5 dB.