| Cable system operators provide bidirectional digital transmission based services to subscribers over hybrid fibre-optic/coaxial cable (HFC) networks. The combined effects of competition, new digital applications, the continued increase in CPU processing power and the convergence of broadcasting, communications and computing require these networks to provide an ever increasing amount of data throughput to each subscriber.; To increase the throughput of transmission over HFC networks, three alternative modulation formats and access techniques are investigated in a quantitative and qualitative manner to assess differences in their implementation and relative effectiveness. The alternatives considered are single carrier quadrature amplitude modulation (SC-QAM), direct sequence code division multiple access (DS-CDMA) and discrete multitone modulation (DMT).; The quantitative assessment is based upon the transmission performance associated with each of the alternative modulation formats and access techniques. Transmission performance is the fundamental criteria for differentiating amongst these alternatives. (Abstract shortened by UMI.)... |
