Method and device for effecting the initial adjustment of the clock in a synchronous data receiver

摘要

In a synchronous data receiver that includes a clock and an adaptive equalizer, a method and a device for effecting the initial adjustment of the clock during a turn-on period in the course of which the receiver is supplied with a known clock synchronization signal followed by a known equalizer training sequence. In accordance with the method of invention, the incoming signal is sampled and the samples so obtained are stored in a storage means. The synchronization signal and the beginning of the training sequence are successively detected. When the beginning of the training sequence is detected, the storage locations for the samples of the received synchronization signal are known and a control signal controlling the initial adjustment of the clock is derived from these samples, which are stored in predetermined locations in the storage means. In a preferred embodiment of the invention, said control signal is derived from the samples that precede the G samples immediately followed by the beginning of the training sequence, the value of G being such that those samples which are in the vicinity of the transition region between the synchronization signal and the training sequence will not be used.