METHOD OF GENERATING A CLOCK SIGNAL FOR THE UPSTREAM CHANNEL OF A BIDIRECTIONAL POINT-TO-MULTIPOINT NETWORK

摘要

A master clock signal generated at the center (1) of a bidirectional point-to-multipoint network is transmitted in the form of time stamps in an MPEG-2 data format over the downstream channel of the network to a plurality of transmitting/receiving facilities (3). Each transmitting/receiving facility (3) derives the clock signal for the upstream channel from the master clock signal and a local clock signal generated by a reference clock (12). The center (1) compares the clock signal from each transmitting/receiving facility with the master clock signal and derives from the result of this comparison digital phase correction information individual to each transmitting/receiving facility (3), which it transmits to the respective transmitting/receiving facility (3) in the MPEG-2 data stream. The respective transmitting/receiving facility (3) uses the phase correction information to control the clock signal for the upstream channel in a numerically controlled oscillator (13).