Design of fixed-point iterative decoders for concatenated codes with interleavers
نویسندگان
چکیده
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-likelihood version (L-SISO), performing sequentially all iterations (an implementation solution coping with medium-low data rate as compared with the hardware clock), and that of a pipelined structure in which a dedicated hardware is in charge of each SISO operation (an implementation suitable for high data rates). We give design rules in both cases, and show that a suitable rescaling of the extrinsic informations yields almost ideal performance with the same number of bits (five) representing both loglikelihood ratios and extrinsic information at any decoder stage.
منابع مشابه
Design of fixed-point iterative decoders for concatenated codes with interleavers - Global Telecommunications Conference, 2000. GLOBECOM '00. IEEE
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 th...
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ورودعنوان ژورنال:
- IEEE Journal on Selected Areas in Communications
دوره 19 شماره
صفحات -
تاریخ انتشار 2000