Design of fixed-point iterative decoders for concatenated codes with interleavers - Global Telecommunications Conference, 2000. GLOBECOM '00. IEEE
نویسنده
چکیده
Implementation rules for iterative decoders of concatenated codes with interleavers are proposed based on a study of the quantization effects on the performance. We consider both cases of a single soft-input soft-output (SISO) module performing sequentially all iterations and of a pipelined structure in which a dedicated hardware is in charge of each SISO operation. In the last case, we show that a suitable rescaling of the extrinsic informations yields almost ideal performance with the same number of bits (5) representing both LLRs and extrinsic information at any decoder stage.
منابع مشابه
Design of fixed-point iterative decoders for concatenated codes with interleavers
We discuss the effects of quantization on the performance of the iterative decoding algorithm of concatenated codes with interleavers. Quantization refers here to the log-likelihood ratios coming from the soft demodulator and to the extrinsic informations passed from one stage of the decoder to the next. We discuss the cases of a single soft-input soft-output (SISO) module, in its additive log-...
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