| 摘要 |
A receiver receives payload data transmitted on a downstream using Orthogonal Frequency Division Multiplexed (OFDM) symbols via a cable network. The receiver includes circuitry configured to receive a downstream signal representing the payload data modulated onto one or more OFDM symbols, and to demodulate the OFDM symbols of each frame to detect and to recover the payload data using the physical layer signalling data. One or more of the frames of the received signal includes a preamble of the frame providing the physical layer signalling data, and in a separate media access control (MAC) signal within the frame, upstream messages relating to the transmission of data from the receiver to the transmitter. Accordingly, an arrangement is provided for a cable network communications system in which a capacity for upstream signalling messages for communicating on the downstream can be adapted to a requirement of receivers connected to the network. |
