| 摘要 |
The present invention relates to a method and to an arrangement for effecting a smooth or undisturbed changeover between at least two binary datastreams (A, B), by minimizing the phase difference between the datastreams prior to changeover. The datastreams are fed into a phase-synchronizing arrangement, where each datastream passes through a respective delay unit (2a, 2b) and is passed further to a switch means (3). According to the invention, the datastreams are tapped to a control unit (4) which is connected between the delay units and the switch means and in which a determined number (23) of random samples (25a', 25b') are taken from the datastreams (A, B). The binary amplitudes of the samples are compared mutually in an amplitude comparison circuit (5c), whereafter a mean value of those samples that have mutually the same binary amplitudes is formed in a mean value forming circuit (5d). The result obtained in the mean value forming circuit forms an actual value (E), which is compared in a comparison circuit (6c) with a predetermined reference value (D). One of the data-streams (A) is thereafter delayed and a new phase-synchronization process is commenced. Alternatively, if the comparison shows that the actual value (E) at least essentially corresponds to the reference value (D), a changeover between the datastreams can take place. |
