Method and circuit arrangement for determining a quality information about the transmission quality of a speech signal in a digital transmission system

In digital transmission systems, for example in mobile radio systems, the voice quality is largely dependent on the correction capability of the channel decoding process. To improve the voice quality error concealment measures are taken, their effectiveness is determined by the accuracy of the information quality of the channel transmission quality. known quality information according to the invention combined and transformed that they are suitable for the error concealment measures as a reliable input parameters. By considering the Bad Frame Indicator BFI in selecting the transformation rules, different transformation rules to the actual transmission conditions can be adapted. The method is easy to implement if a transformation unit in an upstream channel (4) between the channel decoder (1) and error concealment unit (2) is inserted.