METHOD OF TRANSFORMING HFC CATV ANALOG FIBER TRANSMISSION TO DIGITAL FIBER TRANANSMISSION

摘要

A method of converting legacy HFC CATV cable systems, which transmit data over the optical fiber portion of the system using the optical counterpart of analog RF waveforms, such as RF QAM waveforms transduced to corresponding optical QAM waveforms, to improved HFC CATV systems that transmit data over the optical fiber using optical fiber optimized protocols, such as Ethernet frames and other optical fiber optimized digital transport protocols. According to the method, most aspects of the legacy HFC CATV system may be retained, however at the CATV head end, the optical fiber transmitter system is replaced by an improved system that extracts the underlying symbols from legacy waveforms, packages these symbols into optical fiber optimized packets, and transmits downstream. The legacy optical fiber nodes are replaced with improved nodes capable of receiving the packets and remodulating the symbols into RF waveforms suitable for injection into the system's CATV cable.