On turbo codes for environments impaired by impulsive noise

In the recent past, iterative ("turbo") processing techniques with soft-in/soft-out components have received considerable attention. Examples are turbo decoding, turbo equalization, and turbo multi-user detection. The authors consider the application of turbo-codes to environments with impulsive white noise. Impulsive noise has a non-Gaussian nature and is, e.g., found in some wireless channels due to impulsive phenomena of radiofrequency interference and also in power line and in digital subscriber line communication systems. A detector/turbo decoder concept, derived from turbo equalization, is presented. The illustrated concept avoids numerical instabilities. Clearly, the turbo-codes facilitate considerable performance improvements over non-coded systems in impulsive noise scenarios. Furthermore, for benchmarking reasons, the deployment of a conventional rate 1/2 convolutional code with constraint length 5 and octal generators 23₈, 35₈ are taken into account.