Method for the transmission of digital data without a fixed coupling between the clock frequencies and the transmission frequency

摘要

Described is a method of transmitting digital data, in particular audio data, the method calling for the data to be compressed and encoded in an encoder and then transmitted in encoded form, and subsequently decompressed and decoded in a decoder. In prior art methods, the data are passed at an input clock frequency from a signal source into the encoder and fed at an output clock frequency from the decoder to a signal receiver, the input and output clock frequencies being synchronized. The method proposed avoids the need for this synchronization and is thus significantly more flexible in use. The output clock frequency is generated by a controllable oscillator independently of the input clock frequency. The oscillator is controlled as a function of the internal processing status of the decoder, e.g. in dependence on the loading level of the internal data buffer. In another embodiment of the invention, the oscillator is controlled as a function of the difference between the amount of data arriving in the decoder and the amount being output by the decoder, the amount of data arriving in the decoder being determined from the transmission frequency and the mean data rate.