Long-distance Transport of Directly Modulated Fiber Optical CATV System over 100 km Large Effective Area Fiber

Abstract

This study presents a directly modulated 1550 nm NTSC AM-VSB 77-channel fiber optical CATV long-distance transport system using push-pull preamplifier and large effective area fiber (LEAF). Good performances of carrier-to-noise ratio (CNR) 50 dB, composite second order (CSO) 62 dB and composite triple beat (CTB) 61 dB were obtained over a 100 km LEAF transport. Compared with a conventional externally modulated system, our proposed system does not require expensive externally modulated transmitter, sophisticated stimulated Brillouin scattering (SBS)-suppression and differential detection techniques, as well as CTB-predistortion circuit. This proposed directly modulated transport system is simpler and more cost-effective than the conventional externally modulated transport system.