Patent ID: 6947372

Claim:
Multi-carrier communication system wherein data are transferred bi-directionally in a time division duplexed way, and wherein a first pilot carrier whose instantaneous frequency is a fraction of a sample rate of a first transceiver (VDSL_LT) and which is orthogonal to other carriers used in said multi-carrier communication system, is transferred to enable a second transceiver (VDSL_NT) to recover said sample rate, CHARACTERISED IN THAT a second pilot carrier whose mean frequency is a fraction of a time division duplexing frame rate and which is orthogonal to other carriers used in said multi-carrier communication system, is transferred from said first transceiver (VDSL_LT) to said second transceiver (VDSL_NT) to enable said second transceiver (VDSL_NT) to recover said time division duplexing frame rate, said second pilot carrier being different from said first pilot carrier.