Soft decoding in optical systems
نویسندگان
چکیده
We consider the application of concatenated codes with interleaver and iterative decoding to optical communication systems. We show how to obtain the optimum log-likelihood ratio to be provided to the soft decoder in the optical channel environment, and compare the performance of a decoder using it with the one employing a Gaussian approximation of the optical channel. Simulation results refer to practical turbo-product codes, and encompass the effect of quantization on the log-likelihood ratio. The results show that the Gaussian assumption in computing the log-likelihood ratio for the optical channel leads to significant losses.
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ورودعنوان ژورنال:
- IEEE Trans. Communications
دوره 51 شماره
صفحات -
تاریخ انتشار 2003