Methods and apparatuses are provided to modify existing overlay system architectures in a cost effective manner to meet the growing demand for narrowcast services and to position the existing overlay systems for additional future modifications. The implementations of the improved overlay system of this disclosure re-digitize narrowcast analog signals after they have been QAM modulated and upconverted to RF frequencies and replace the analog narrowcast transmitters with digital narrowcast transmitters. In the fiber nodes, the received narrowcast signals are converted back to analog signals and combined with analog broadcast signals for transmission to the service groups.

Methods and apparatuses are provided to modify existing overlay system architectures in a cost effective manner to meet the growing demand for narrowcast services and to position the existing overlay systems for additional future modifications. The implementations of the improved overlay system of this disclosure re-digitize narrowcast analog signals after they have been QAM modulated and upconverted to RF frequencies and replace the analog narrowcast transmitters with digital narrowcast transmitters. In the fiber nodes, the received narrowcast signals are converted back to analog signals and combined with analog broadcast signals for transmission to the service groups.

Performing distributed Remote PHY scheduling operations. A low latency scheduler is disposed within or in proximity to a Remote PHY node. Upon identifying that a particular data flow qualifies for processing by the low latency scheduler, the low latency scheduler performs upstream Remote PHY scheduling operations for the particular data flow using a one or more dedicated channels that are designated as low latency channels. The Remote PHY upstream scheduling operations define when data may be transmitted by a Cable Modem (CM) to a Converged Cable Access Platform (CCAP) Core. A centralized scheduler is also located at the CCAP Core. The centralized scheduler performs Remote PHY upstream scheduling operations for all data flows which have not been identified as qualifying for processing by the low latency scheduler.

Performing distributed Remote PHY scheduling operations. A low latency scheduler is disposed within or in proximity to a Remote PHY node. Upon identifying that a particular data flow qualifies for processing by the low latency scheduler, the low latency scheduler performs upstream Remote PHY scheduling operations for the particular data flow using a one or more dedicated channels that are designated as low latency channels. The Remote PHY upstream scheduling operations define when data may be transmitted by a Cable Modem (CM) to a Converged Cable Access Platform (CCAP) Core. A centralized scheduler is also located at the CCAP Core. The centralized scheduler performs Remote PHY upstream scheduling operations for all data flows which have not been identified as qualifying for processing by the low latency scheduler.

A plurality of digital video recorders are polled to extract data indicative of recordings scheduled thereon. The polling is carried out over a video content network by a component at a node in the video content network that is remote from the plurality of digital video recorders. At least a portion of the data is used to obtain a prediction of future switched digital video channel usage for the video content network. At least one network management activity is carried out on the video content network in response to the prediction of future switched digital video channel usage for the video content network.

A plurality of digital video recorders are polled to extract data indicative of recordings scheduled thereon. The polling is carried out over a video content network by a component at a node in the video content network that is remote from the plurality of digital video recorders. At least a portion of the data is used to obtain a prediction of future switched digital video channel usage for the video content network. At least one network management activity is carried out on the video content network in response to the prediction of future switched digital video channel usage for the video content network.

Systems and Methods for reducing distortion due to bursts of upstream transmission in an HFC CATV network. In some preferred systems, the functionality of an Optical Network Unit (ONU) may occur within a node or amplifier along a direction upstream from a subscriber's home.

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.

A multi-transceiver configuration method, a multi-transceiver channel multiplexing method, and an apparatus are disclosed. The multi-transceiver configuration method includes: an access point obtains maximum data transfer rates R.sub.i(n) of N terminals STA.sub.is on sub-channels n in a specified sub-channel combination, where 1≦i≦N, and N is a positive integer greater than 1; and calculates a channel access time T.sub.i(n) required by the STA.sub.i for transmitting an average data volume on the sub-channel n, and when the specified sub-channel combination manner meets an allocation requirement of the N STA.sub.is, the access point configures at least one transceiver for each sub-channel n in the specified sub-channel combination.

An optical network includes a transmitter portion configured to transmit a digitized stream of symbols over a digital optical link, a mapping unit disposed within the transmitter portion and configured to code the transmitted digitized stream of symbols with a mapping code prior to transmission over the digital optical link, a receiver portion configured to recover the coded stream of symbols from the digital optical link, and a demapping unit disposed within the receiver portion and configured to map the recovered coded stream of symbols into an uncoded digitized signal corresponding to the digitized stream of symbols at the transmitter portion prior to coding by the mapping unit.