Digital subscriber's line transmission manner, from the transmission device, the transmission system and the xDSL

摘要

A digital subscriber line transmission method and apparatus for transmitting downstream data from a device on an office side to a device on a subscriber side and upstream data from the device on the subscriber side to the device on the office side over a single line by switching between these data transmissions in time-division fashion, dividing data of one symbol, modulating carrier waves having different frequencies by each item of divided data and frequency-multiplexing the modulated signals, and transmitting the frequency-multiplexed signals in bursts a few symbols at a time, comprising: generating a pilot-tone signal with which synchronously processing is executed; making the length of an interval in which a signal is not being transmitted (Ta) between contiguous transmit burst symbol sequences (500) a whole-number multiple of the cycle of the pilot-tone signal; and assuring continuity of sample data in contiguous transmit burst symbol sequences by executing processing in sync with the pilot-tone signal.