| 摘要 |
<p>The invention relates to a system that is suitable for bidirectional communication via the electrical network between a headend and numerous users. Said invention can be used for both time and frequency synchronisation of multiple users in an OFDM (Orthogonal Frequency Division Multiplexing) multi-carrier communication system. The inventive method is characterised in that it consists in generating synchronisation sequences using two identical synchronisation symbols (16) which are transmitted periodically from the headend equipment by means of the downlink to the users. The sampling frequency can then be determined and corrected and, simultaneously, the moment at which the OFDM symbol starts can be determined, such that the samples of the signal received by each user match those used in the transmission.</p> |
