EXIT-Optimized Quantizer Design for Iterative Source-Channel Decoding

In digital mobile communications the input speech, audio, or video signal has to be quantized before transmission. In this paper, we propose a novel quantizer design strategy which is optimized for the case that iterative source-channel decoding (ISCD) is applied at the receiver site. The combination of the new quantizer with the ISCD scheme reveals a substantially increased error robustness in bad channel conditions at the cost of a tolerable loss of baseline performance in almost error-free situations. This trade-off can smoothly be adjusted.