The transmission scheme of DAB was especially developed to allow a mobile reception under multipath propagation conditions. This means that the requirements on the protection of the digital encoded audio bitstream against bit errors are very high. The influence of residual bit errors on the subjective degradation of the audio signal depends on the error protection strategy.In this contribution the error protection realised for DAB is described:1. the principle and performance of unequal error protection on the base of punctured convolutional codes,2. the influence of additional error detection for the application of error concealment techniques,3. the realised protection schemes for the digitally encoded audio signals which are designed with respect to the subjective annoyance of bit errors in the audio bitstream, and4. the various error protection levels within DAB which allow a trade-off between high audio data rate and high transmission reliability or large service area, respectively.
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