In this paper, a reducedcomplexity Log-MAP algorithm based on a non-recursive approximation of the max* operator is presented and studied for turbo trellis-coded modulation (TTCM) systems. In the algorithm, denoted a...
详细信息
In this paper, a reducedcomplexity Log-MAP algorithm based on a non-recursive approximation of the max* operator is presented and studied for turbo trellis-coded modulation (TTCM) systems. In the algorithm, denoted as AvN Log-MAP, the max* operation is generalized and performed on n >= 2 arguments. The approximation is derived from the Jensen inequality. The non-recursive form of the max* calculations allows to achieve significant reduction in the decoding effort in comparison to the conventional Log-MAP algorithm. Bit-error rate performance simulation results for serial and parallel TTCM schemes in the additive white Gaussian noise and uncorrelated Rayleigh fading channels show that the AvN Log-MAP algorithm performs close to the Log-MAP. Performance and complexity comparisons of the AvN Log-MAP algorithm against the Log-MAP and several relevant reducedcomplexity turbo decoding algorithms proposed in the literature reveal, that it offers favorable low computational effort for the price of small performance degradation.
We have investigated an adaptive reliability-based iterative soft-decision Reed-Solomon decoding algorithm using belief propagation and we propose a reduced-complexity version of this algorithm. We discuss implementat...
详细信息
We have investigated an adaptive reliability-based iterative soft-decision Reed-Solomon decoding algorithm using belief propagation and we propose a reduced-complexity version of this algorithm. We discuss implementation and,performance evaluation of these algorithms on magnetic recording channels.
In the paper, a modified Log-MAP algorithm based on a novel approximation of the max* operator derived from the Jensen inequality is proposed. In this approach, the max* operation is performed on n >= 2 arguments, ...
详细信息
ISBN:
(纸本)9781424480166
In the paper, a modified Log-MAP algorithm based on a novel approximation of the max* operator derived from the Jensen inequality is proposed. In this approach, the max* operation is performed on n >= 2 arguments, thus the recursive calculations are avoided and significant reduction in the number of operations performed per decoding step, as compared with the conventional Log-MAP, is achieved. Simulation results of BER performance for both turbo codes and turbo trellis-coded modulation (TTCM) employing the new algorithm are given, showing the near-optimal performance of the proposed algorithm.
暂无评论