摘要 |
In connection with plesiochronous data transmission, data are input into an elastic memory on the basis of a first clock pulse and read out on the basis of a second clock pulse which runs asynchronously with the first. Stuff bits are inserted at the end of a data frame as needed. For this purpose, the phase difference between clock pulses within a data frame is first of all measured. This phase difference is then compared with a threshold and a certain number of stuff bits are correspondingly inserted. In accordance with the invention, a frequency difference existing between the clock pulses is measured and, depending upon in which of several specified segments it lies, a correspondingly predefined modulation curve is used as threshold. Preferably a numerically optimized curve with respect to jitter amplitudes is used for each segment.
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